Slashdot Mirror
Is A Catch-All Address Worth The Spam?
wildzeke writes "I plan on switching Internet providers this summer to get a faster speed. Since losing an email account is the biggest pain when switching providers, I decided to pay the extra money to have email for the domain I registered. One of the options provided is to make one of your email accounts a catch-all account. In other words, any email sent to this domain with out a valid user name, will be dumped in the catch-all account. The question I have, is this a good idea or not? On one hand, it may catch important email such as admin, or postmaster or simply mis-typed user name. On the other hand, the catch-all will open the flood gates to spam who will send to [all user names in the world]@domain.com."
If the mail is from an intelligent human being they will generally conclude from the returned mail that they have erred, and readdress it accordingly. In the event of any other outcome you are probably better off not receiving the mail.
Buying your own domain is a smart move. As long as you keep paying for the domain, your e-mail address can travel with you, even when you change ISPs.
From personal experience, I've found that only a very small percentage of spam I get comes from using the catch-all address. I get only a few junk e-mails to "webmaster", "postmaster", and other generic usernames. A far greater portion of it is addressed to the "real" e-mail address I use that's been plastered all over the web for years and years.
Judging only from my inbox, it would seem that spammers are more likely to use lists of known e-mail addresses than trying to guess valid usernames for a domain. My advice would be to use the catch-all address and just wait and see if spam becomes a problem. Turning off the catch-all wildcard, if need be, is a very simple operation.
If you use a spam filter, you sould not have to worry about it. You are not exposed to more kinds of spam, just more instances. And since spam filters currently have no issue with volume, you should be ok.
who | grep -i blond | date cd ~; unzip; touch; strip; finger; mount; gasp; yes; uptime; umount; sleep
just be glad you're not asdf@asdf.com.
set it up, but make sure you have a good bayesian filter to weed out the crap.
if anyone really emails your domain, and it bounces, won't they figure it out?
Seems like a useless feature.
read the title. FP?
I can't understand some people, sometimes spam makes so exciting reading...
Doesn't matter, the only stuff sent to other addresses is spam
now if you want to know how you got the e-mail, based upon what email address they used, then it's helpful
What does it matter if it opens you up to spam. It's a catch-all account right, isn't that what it's supposed to do?!?
..and don't forget to send the spammer's IP to the spam blacklists automatically.
Maybe you could set one of those up and use all the spam detection software you can find (i.e. Spamcop) i'm sure other people will post the URLs to some spam detection software which you can run on your server. That way you get to reduce the ammount of spam that you have to sort through while searching for legit emails. Most of the spam these days is ovbious spam like Subjects which make no sense and often have lots of spelling errors in the body. Beacuse of this you can detect spam by hand quite easily too.
Have you metaroderated recently?
If your catch all address forwards to your personal mailbox, your antispam solution should still filter the junk no matter where it's sent. In fact, you should probably be able to ratchet up the spam rating a bit for anything which is not sent to your personal account, and give yourself a bit of a head start...
I do it. I've found that although a lot of spam gets sent to that email, people aren't going to just send adsflkjes3542@domain.com an email. Randomly guessing email doesn't get you a hit. Most spam kings purchase emails. Why? Because they need valid emails.
You're opening your gates to nonvalid emails, but that doesn't seem to be a threat. As stated earlier, no one wants nonvalid emails.
As someone who has been using a catch-all account for years, and has enjoyed the benefits and suffered the consequences, I would suggest you do it (though not without some warnings and recommendations). I do receive a fair amount of SPAM for accounts which have never existed on the system. I have also endured several periods when some SPAMmer referred to fake accounts at my domain in the return-to of the SPAM they were sending out (they were not using my mail server, they simply made up random usernames for my domain). Since they were random (both the names they used and the content of the SPAM) it was impossible to easily filter out. That sucked. I would receive hundreds of bounce messages per day. Ultimately I was able to make it stop by writing a script to post every bounce message I received through to the support form on the websites being advertised (modifying for each of the three or four sites which were involved), making the normal "cease and desist" legal threats. It seemed to work, since the SPAMs did stop soon after (presumably those sites complained to the SPAMmer they employed), and the SPAMmer no doubt moved on to some other fake accounts. Bastard. One of the best features of the catch-all is that you can totally control to whom you give out your "real" e-mail address, as well as track who is using the e-mail addresses you are giving out. For example, if you want to register at example.com for something, you give them the address me.example@yourdomain.com (or some structure which has a prefix or postfix, the 'me.', and the site name for which you are registering). You'll be able to receive that sites mail until you either don't want to, or until you see that they have abused the privilege of e-mailing you. Often I will see six months after registering to some site, I start getting tons of SPAM from the e-mail I gave to that site, and I can then simply block that on the mail server, bouncing them or sending them to /dev/null (via aliases, for example). This is the greatest strength in using catch-all addresses.
To mitigate the danger I mentioned previously of fake usernames, one should (though I am no sendmail expert and don't know how) set up a rule that any incoming recipient address must correspond to an existing account/alias, OR the catch-all structure you want (the whole PREFIX.SITENAME@yourdomain.com).
Q
Don't vote for Eugene Papansanovich for Congress!
I just write mail back. It's rather funny when you get a reply from the spammer. That isn't automated.
I'd say that people will have a harder time remembering 'just put down anything you want @mydomain.com' than telling them specifically send it to 'joebob@mydomain.com'. Thus that kind of cancels out the advantage, and still leaves you ripe for spammage.
Incidentally, first post (albiet it's probably been taken by the time I'm done typing this...)
Not at all.
The ideal setup is to have several addresses.
One for close friends, associates, individuals and people who the address is sent to privately.
A second address for mailing lists, and any kind of public posting.
And a third address for anything guarenteed to end up in you getting spam. (Website signups for instance)
Then you simply drop it into three different folders. This method combined with a good spam filter can eliminate virtually all spam.
It is great. You never have to worry about giving out an indiscriminate address again. Signing up for a fantasy league on cnn/si? I used cnnsi@mydomain. cnnsi sold it and now I get several hundred spam a day there. And I can trivially filter and nuke them, with the added bonus that I know never to send them my business again. amtrak has amtrak@mydomain, I get all the mail from it, and can easily track that they have never violated their TOS. It's the greatest thing- I heartily recommend it to anyone who can.
IAAL,BIANLY
No
Then every time you sign up for something create a new email address. Thene you can figure out who is selling your address, filter out that particular address, and so on. It makes managing your email and filtering out spam much easier.
i get lots of spam to my catch all address - lots of names form some dictionary probably. but you can switch the catch all adress off if shit happens.
SHE does throw dice.
I fought it for a year or so, coding up custom filters, using spam assassin, you name it, and finally just gave up and blackholed it.
Spammers are trying dictionary attacks against domains to try and guess live accounts. I would get 500+ copies of the same message to made up names in alphebetical order a day.
That being said, I have since gotten on the Gmail beta, and just forward all my mail there now. It has a far better spam rejection rate then anything else I have tried, so if you forward all your mail to a google account and let them try and sort out the spam, it would probably be usable (and maybe even helpful to them to train their filters).
Mathematically impossible requirements are technically not against policy.
On the other hand if you leave the * account on, you don't need to creat a new account eact time you need one. I for instance only have one account on my mail server and that is the postmaster this allows me to invent e-mail addresses on the fly.
With this ability you can make an e-mail address for each use of your e-mail for sites and forums like Slashdot@Domain.com and if you start getting spam at that address you can quiet happily block it via the filter.
I type a@b.com
I have one of my e-mail addresses configured to catch all the "bad" addresses as you are talking about. There is an extraordinary amount of crap that account gets every day. It really isn't worth it, especially if you have the admin and postmaster addresses dump to your primary mail account.
This sig seemed like a good idea at the time....
so, if you get spam on this specific address you know where to complain.
...and I get very little spam (maybe 10 a day) directed to anything@mydomain.com, whereas my regular address gets around 150-200 a day. Thank goodness I have Postini and Thunderbird.
I say go for it, because you can use filters to direct different addresses to different folders, which can be useful.
You are in a maze of twisty little passages, all alike.
As a geek, I run my own mail server. A "catch all" that goes to /dev/null is great.
"Who are in control, they are not in control of anything - they don't even control themselves!" - Glen Beck
If you're worried about missing e-mail to 'important' accounts, just forward them to your real address. Don't bother with the catch-all. In fact, if you have the option, have it black-holed rather than bounced.
The best way to go would be to start with the catch-all, and once you get fed up with it, disable it. You'll feel a real sense of accomplishment when you see how much spam you stop.
I've had a catch all address for over 4 years now...and whilst I get a fair amount of spam to that domain (just over 100 messages a day), the majority of those are to one real address I used years ago - and haven't used since. The rest is either to the main address I use, fairly standard guesses "sales@", "info@", "webmaster@", etc...or to one or two addresses that spammers seem to have made up, but have stuck. one of them is a misspelling of my name, another is "tressia" which I have no idea where that came from. But I definitely don't see "all usernames in the world"@mydomain
Advanced users are users too!
I tried this with my email account, just in case an important mail went to another address. The day someone decided to spam *@mongeese.org, I killed that option. Some spam bot prefixed random names to @mongeese.org. Needless to say I ended up with around 300 emails one morning. All with the same bodies but different email addresses. I'm suprised it wasn't more than 300, I figured a spam bot would try sending to more names than that.
Outdoor digital photography, mostly in New Engl
I run several catch-alls on my domains for several years, and I've never been spammed at [all]@[domains].com. However, just last week all my domains were hit by an email virus that did a dictionary-based attack. While it was all still caught by my spam filter, my spam filter is client-side, and after downloading 18200 emails, I decided it was time to shut down the catchalls.
The only thing I really had to do was notify my friends, who are long used to typing whatever they want into the username section of the domain, tailored to whatever it is they want (eg boywhowillfixmycomputer@, bikemechanicmanwhowillalsofixmycomputer@ etc).
Just wait until the spambots launch a dictionary attack against your domain...
In my limited experience, most of the dictionary attacks come from IP's that traceroute back to Singapore. Just blocking all incoming SMTP from Singapore IP's would be smart but I don't know how to do something like that.
I set it to bounce such emails... it makes the spam less effective and a valid sender would realize a typo and resend the email with correct address
I do that, and I also use a dummy account for each new place I have to register (such as newyorktimes@mydomain.com). That way, I know who sold/lost/traded my address, and if I start getting lots of spam to it, I can actually create that account, and have all mail sent to the trash at my hosting service.
Yes, it's worth doing.
From personal experience, this seems to be working well. I only get a handful of spam sent to random addresses at my domain.
Other folks may have different experiences, but this is what I have found and I usually get 500+ spams daily accross my personal domain email accounts.
SPAM solution made easy: 1 spammer, 5 cords of rope, 5 hourses, and fireworks. Be creative.
I have a catch-all address at my domain. YES, there are huge amounts of spam. BUT, it is definitely worth the trouble IMHO, and here's why.
1 - most of the spam seems to come to 5 or 6 addresses only - admin, root, sales, webmaster, etc etc. That's cake to filter out straight to trash.
2 - The convinience of being able to sign up for random websites with a different address on the fly is great. For example, signing up on ebay to buy something and using the address "fromebay@mydomain.com" means you KNOW that only one person in the world has your email address so you know who to blame if spam starts coming in, and it is also a piece of cake to automatically filter those ebay emails straight to an ebay inbox, for example.
3 - Not as significant as my first 2 points but still a nice perk in my setup is that I'm able to create email addresses for family and friends on the fly and just setup my own server to split the addresses out into their own inboxes.
So if you will be running the server(s) yourself over slow dsl or cable, the volume of spam MAY be a concern to you. I get about 600-700 spams a day to the common webministrater addresses I mentioned, but it's no concern to me because I don't run the incoming email server and my dsl is more than fast enough to d/l them in a few seconds.
But in any other case, I'd say it's well worth it! And on a slightly different note, I have been very impressed with the honesty and adherence just about everywhere has to their privacy policies regarding email addresses. over 2 years of using my system with about 50 "from@domain.com" addresses, only one of them screwed up and got the address on a spam list somehow - cancelling my account with them and filtering those spams straight to trash solved the problem.
"This is Zombo Com, and welcome to you who have come to Zombo Com" - www.zombo.com
I've been running my own mail account off of my own domain for about 2.5 years now, and I don't regret it. I do have the catch-all set to dump to my personal account, and it's not been a major problem. Most of the spam I get is addressed to a "real" address (either mine or one of my older accounts I have forwarded to me), and there's a lot of that, so the amount I get from the catch-all is negligible.
:-)
In practice, actually, most of the spam-related stuff I get is mail bounces attempting to a random address with a faked from line of 63745624573@mydomain.com (or something like that). I really should look into implementing SenderID, but that would require hosting the server myself on a my dynamic IP instead of letting my web host take care of it.
--GrouchoMarx
Card-carrying member of the EFF, FSF, and ACLU. Are you?
From my personal experience I've been getting a LOT of spam lately which is addressed to "made up" addresses at my domain. Either an awful lot of people lately have been giving out fake email addresses at my domain or spammers are somehow making them up from reasonable sounding usernames that never existed at my domain.
My webhost (which is where I do my e-mail) is the same way by default. It's catch all, then you just deny the addresses you don't want. So I used to do it like that. If an address started getting SPAM, it got on the ban list.
Well between the new viruses and SPAM tactics that try random first names, that wasn't at all working. So I flipped the mode. Now NOTHING gets forwarded, excpet for ones I specify. This means I have to go add a new forward before giving out a new e-mail to a compnay whereas before I'd just make one up, but it works just as well. If I get SPAM to one, I just shut it down and am done with it.
If they'll let you do that, it should work well for you.
I've gotten maybe a dozen spams with "made up" to: fields. I think the OP is over-analyzing all this.
I currently forward all registered domain emails to my regular email which I check almost hourly. All of the rest are forwarded to, either another account, or something like Gmail. Works for me.
Then, when you get spam, just send them a bill.
When they don't pay, I'm sure you can get a judgement against them. Hell, you could probably put them on a list of dead-beat spammers and get them arrested eventually!
AC comments get piped to
Spam really isn't the biggest problem i have with the domain mail -- as others have said, most spam will actually go to the addresses you actively use.
Use an email service that offers server-side spam and virus filtering and it'll be nothing to worry about. I use Fastmail.fm, and they use spamassassin and some AV service. It's great, cut down about 95% of the junk I used to get, and it's TOTALLY geek-friendly so you can customize it however you want or turn it off if you are a masochist.
The thing that is annoying are all the "error" messages i get from email servers because some virus attached some randomly generated name to my domain when sending out copies of itself. I can't very well automatically delete mail bounce messages, so i have to actually LOOK at those to make sure it wasn't something real.
Recursive: Adj. See Recursive.
I've had a catch-all for years and I like it. I get a bit more spam than otherwise, but the thing I like is the ability to filter incoming mail based on how it's addressed. If I buy something online I always use $company_name as the address: "newegg@domain.com" for instance.
The catch-all means that I get this email. After I filter for spam, I have all mail sent to my primary, real, address put in one folder, and everything else in another.
You can filter by sender too, but this reverses the problem. As it stands I can proactively filter on my primary address instead of playing whack-a-mole by sender.
This isn't as much "normalization" as it is "don't take so many drugs when you're designing tables."
I pay Namezero $25 a year for my own domain... it comes with 3 (or so) pop3 accounts and unlimited email alias's along with a "catchall" alias... I use it all the time when registering for a site aka slashdot@mydomain.com. If the spam becomes too much, and it's just on that paticular address... i know who sold me out and I simply setup an alias via Namezero called slashdot@mydomain.com and forward to to the sites administrators email address.
What was your username again? -BOFH
I had a catch all account set up on both my domains, and I was recieving up to 4000 spams a day before I had had enough and switched it off - I don't care how good your filtering is - when the spam:legit email ratio is that high it's difficult to trust, and for that matter is a waste of bandwidth - Yahoo's POP3 server would also tend to fail if I had to download more than 200 at a time anyway.
You don't want a catch all email address - the only time it's ever been used by a human being was when they thought it would be funny to include some of the message before the @, etc.
Use a +* alias entry instead. This way, you still have a catchall, but it only "works" with the start of an address, and if the spam becomes unbearable, you can junk it totally and start afresh.
is this a good idea or not?
No, it's not a good idea. Looking through my mail server (and other mail servers I administer) I've seen A LOT of attempts by spammers to harvest email addresses by just trying a lot of common names on the domain (and some strange not so common addresses). If you had a wildcard address, you'd get all that spam to that box.
With no wildcard email address if people miss-spell a name on your domain, they'll get a prompt bounce message (and they'll probbably figure out the miss-spelling). With a wildcard they'll never figure out the miss-spelling, and may continue to use that wrong address.
There's also the problem of auto-generated virus bounce messages from other peoples servers. Most viruses lie about their from address, and can even make up a @yourdomain.tld. If you had a wildcard all those erroneous "you sent a virus" messages would go to your wildcard box instead of just bouncing.
Unless you want an account that's deluged with spam and like wading through it every so often on the off-chance someone sent a message to admin or postmaster, I'd not create a wildcard box.
AccountKiller
Every time someone would ask for your Email adress, you'd just come up with a new one, that would be kickin' rad in my opinion.
And also, it would be interesting to see if people actually use your domain as a dummy mail (considering it's a fairly easy/funny domain).
All I can suggest is to give it a try for a while (couple of months, a year) and see what happens. If you get a ton of spam and no important email, then turn it off.
When I had my catch-all account, I rarely got any spam, and that's probably because most spammers won't really bother with trying to send you something at afhg329087dsfljifd90hlg@domain.com or whatever.
Thunderbird is amazingly powerful at filtering spam after some training. It should help cut down on the hassle.
Just so you know, that e mail address wont work....
http://www.asdf.com/asdfemail.html
I think it's best to just reject mail addressed to non-existent users during the SMTP transaction. My outside relay uses Postfix's relay_recipient_map to validate all recipients before relaying inside... anything not matching gets rejected with a 550. This saves my content filters (amavis/clamav) alot of work since we get TONS of spam to non-existent recipients.
e cipient_maps = mysql:/etc/postfix/mysql-recipient.cf,t = relay:mx2.somethingawful.com
relay_domains = mysql:/etc/postfix/mysql-relaydomains.cf
relay_r
mysql:/etc/postfix/mysql-alias.cf
relay_transpor
If you don't validate recipients, then you probably SHOULD use a catch-all address. The alternative to this would be bouncing spam back to the (usually forged) sender, in which case you become part of the problem and can cause yourself major queueing problems.
UNIX? They're not even circumcised! Savages!
I recently switched to using e-mail from my registar/hosting company, they included one free address and I paid for an additional 5 mailboxes.
I set up an account for myself and my wife, and used the free account for a spam bucket. My account is set up as a catch-all. Whenever I sign up for something I use and address in the form slashdot.org@<mydomain>.com so if it does start getting spam I know who sold my e-mail address.
If any spam comes in being caught by the catch-all I set up a forwarder to my spam account. For example dns@<mydomain>.com gets forwarded to spam@<mydomain>.com I then just set up my e-mail client to dump anything that comes in via the spam account directly into the trash.
To date I have received spam on three addresses that didn't really exist (dns@, sales@ and info@), but overall it works very well.
I host my own personal domain (something like johndoe.com) with a hosting company. I had a catchall account, and used it to great success when giving out my e-mail addy. (For example I'd give stores their own name: homedepot@johndoe.com, walgreens@johndoe.com, etc. Not these specific example, but you get the gist.)
:(
Anyhoo, somehow, someway, somewhy, a spammer got ahold of my domain. And they created just about every possible name you could imagine for my domain: janey123@johndoe.com, rty5632@johndoe.com, ricksmith@johndoe.com, etc. Of course, it's just me at the site. But I suppose they didn't care. To make a long story short, I started getting over 1,000 spam messages per day in my catchall. And now it's grown exponentially. The assholes even send the same spam to the same addy, like, ten at a time. So basically my domain is fucked. And of course, once you get on some dumbass spammer list, they ALL start sending it to you. I've had my catchall account turned off for the last several months, and it's set to bounce back. But it makes no difference.
Every month or so I turn it back on to see if they've given up, but it's just more and more and more of the same. Until a cure for spam is found, I'm dying over here. It makes my e-mail almost useless. Sheesh. Please someone do something about this stuff.
Hopefully this won't happen to you, but if it does, you're screwed.
'nuff said.
I recently narrowed down my catch-all e-mail address to a handful of addresses I actually use. Before the switch I was averaging 1,200 spam a day. After the change I am averaging 300 spam a day.
My suggestion is to find a forwarding service that allows you to set a list of what gets sent and what gets blocked.
Where would we be if Wheel had hid her round rock in a cave instead of showing everyone how it rolls?
In my experience a catch-all has worked out well. While I do see dictionary attacks constantly at work, I don't think I have ever seen one on my personal domain. I am not sure why, but I can think of many possible reasons. One being that I have a .org instead of a .com or .net. In that isps with lots of customers use .com or .net, but generally not .org. Another is that there may be some minimal number of addresses from the same list for them to dictionary attack it. Overall my domain doesn't seem to really be on the spammers' radars. I do get spam to root@, postmaster@, sales@, etc.
An even better method than a classic catch-all would be a extension catch-all. ie something+(anything)@domain.com instead of (anything)@domain.com. An example jsmith+amazon@domain.com. You can do this with many MTAs and the two most common extensions are + and -. - will work more universally, but if users want some-thing@domain.com as an e-mail address it won't work with - as the extension. Supposedly a few uncommon e-mail clients, and a few very uncommon mtas have a problem with it.
The best method I have for cutting down spam is a greylisting, http://www.greylisting.org/. It cut spam down in volume from 10x real mail to 1x. So instead of 90% of mail being spam, 50% of mail is spam.
Havoc Penington, the bane of my Linux desktop.
They're bloody cheap and'll do anything an extra few cents..........
DK
Greece is the Word
I had to turn all my catchalls off (for several domains) because when a spammer decided to spoof my domain, I got several hundred spams A MINUTE that bounced bak and flooded my inbox. This happened several times (i.e. toeach of my domains) and in the end I had to turn off all the catch alls to stop the flood of spam bounces. Hundreds a minute! Those were a few bad days.
Seriously, I was worried about having a "*@samsimpson.co[m|.uk]" e-mail catch-all and getting tons and tons of spam. In reality (after 4 or so years) I always get mails to my externally used addresses (sam@ & delme@). I never get mails to any other address in my domain.
Having a catchall address is nice because it allows you to register at websites with sitename@domainname.com and still get the mail (and notice instantly if they sell on your details).
"Mary had a crypto key, she kept it in escrow, and everything that Mary said, the Feds were sure to know."
I also use the method of giving out lots of different E-mail addresses to track down who sells my info. Those who say, "you can always turn off the catch-all" are missing the point, because those of us using this method don't usually remember all the addresses we've given out, and therefore, using a "whitelist" isn't practical. Now, this system works great as others have said. You get a few occasional spams to things like webmaster@, sales@, info@, etc. but those can be easily filtered. The big problem is with annoying worms that generate random E-mail addresses. Of course, all of them get sent to your catch-all account -- in one day I got 150 Zafi.B worm E-mails from somewhere in Mexico. When you get one of these, what do you do? If you don't bounce the message, it's likely that the randomly generated E-mail address will be treated as valid and added to some spammer's database. Sure, you can blacklist each address, but then you're playing catch-up to a random generator algorithm. Not likely to win at that kind of game. Anybody know a good way to generate bounce messages in this kind of situation? Most mail bouncers assume you have only one address, and they create dangerous bounce messages that carry your *real* (i.e., desired) return address. I need a bounce script that grabs the "Received from... for ____" header and uses that to generate a bounce as if it originated from the randomly generated E-mail address. Can anybody help? PLEASE? Thanks!
If you're just using it for personal email, I can't say there's a big reason to have a catch-all address. It's been nothing but a hassle for me. (One of these days I'm going to get around to fixing that.)
Figure I might as well share a little bit more with what I do with my email. I have two domains, one's a personal domain, the other is for a project I never got off the ground. I use the personal domain for my personal email etc. Unfortunately, I do have a catch all on that, and it's rather obnoxious. I do have spam filtering, but junk still gets through. Don't really have time to muck with it, ya know? All I need to do is crack down on the address again. Just haven't found the time.
On my other domain, I'm currently using it as a forums email box. It's locked down. It only has a few valid email addresses, the rest are trashed. I have one mail account with a ton of forwarders leading into it. If I register with NYTimes, then I set up a forwarder from nytimmes@thenameofmydomain.com to forumbox@thenameofmydomain.com. If I sign up for Slashdot, then Slashdot@thenameofmydomain.com is forwarded to forumbox@thenameofmydomain.com. So each place I sign up for has its own address. If I start recieving spam from a particular address, then I just turn off the forwarder. Result? I don't even need to be running Spam software.
My forums domain does a much better job of handling the spam/communication features than my personal domain with the catch all.
"Derp de derp."
Now, this system works great as others have said. You get a few occasional spams to things like webmaster@, sales@, info@, etc. but those can be easily filtered.
The big problem is with annoying worms that generate random E-mail addresses. Of course, all of them get sent to your catch-all account -- in one day I got 150 Zafi.B worm E-mails from somewhere in Mexico. When you get one of these, what do you do? If you don't bounce the message, it's likely that the randomly generated E-mail address will be treated as valid and added to some spammer's database. Sure, you can blacklist each address, but then you're playing catch-up to a random generator algorithm. Not likely to win at that kind of game.
Anybody know a good way to generate bounce messages in this kind of situation? Most mail bouncers assume you have only one address, and they create dangerous bounce messages that carry your *real* (i.e., desired) return address. I need a bounce script that grabs the "Received from... for ____" header and uses that to generate a bounce as if it originated from the randomly generated E-mail address.
Can anybody help?
PLEASE?
Thanks!
I had a problem where I gave one of my friends an account on my domain. He used it to sign up for various things and eventually stopped using it. After awhile I started getting undeliverable messages to my catch-all account, they were all related to his account. I think it had filled up and was bouncing messages. I asked him if he was using it anymore and he said no, so I deleted the user. Then my catch-all started getting dozens of spam messages a day.
When I hosted my domains I just had a few 'standard' addresses at the domains going to a 'stuff' mailbox. Aliases like:
- root
- webmaster
- postmaster
- admin
I thought it was better when people use other non-existent addresses that they get a bounceback rather than mail being accepted. Especially with the newer worms/trojans that forge headers to send out mails from blahblah81@yourdomain.com etc.
Uh, sorry, but that sounds just like the legitimate e-mail I get from some of my friends... :o)
--
Tomas
But I think it depends on what you are using your domain for; wildcard spam is minor/rare compared to targetted spam:
If it is a personal domain with perhaps a couple of description pages and even a blog then, like me, you will get no more (from personal experience) than 10+ random (random in the way they are sent to webmaster/admin or anything that * catches other than regular) messages/week. No big deal
A better known site seems to get a greater ranking in auto-traffic (let me generate logos, banners, security, etc for your website). But an email address listed on the site (my site) gets far more spam than a generic catch-all (e.g., I have "email webmonster@....com" as the auto admin address, more emails come to that than webmaster coz it's googled/harvested on those lists).
But the original statement said "I decided to pay the extra money to have email for the domain I registered" WFT?! Go to something like directnic.com, get your domain for $15/yr and get mail forwarding included (including wildcard)!
If this is for just personal use god do NOT bother it isn't worth it, no way no how.
Business? Yes unfortunately I would, actually, I do. See, people have this ANNOYING habit of just emailing "stuff"@domain.com asking sales questions or support questions, or whatever. I get emails to sales, admin, billing, suppost, administrator, postmaster, and as sure as I ain't monitoring something, someone will just decide for some reason or another to email like "web@" or something equally silly and unused. The offchance of missing a pre-sales or post-sale support question just isn't worth it.
So I run with bayesian filters, RBL's, and other goodies to try and minimize spam, it's not too bad about 6 per day get through, this is just short of amazing. I'll see maybe, 1 or 2 false positives (real mail marked as spam) per month.
If this were a personal setup, no "money" involved I'd NEVER use the catch-all.
--- www.f-theocean.com
As noted by others, using a catch-all can be a great way to guard against spam by using it as a spamtrap.
.
E.g. sign up for Slashdot with slashdotorg@mydomain.com
If Slashdot were to ever hand out the e-mail address, just block it.
This doesn't prevent you from becoming the victim of somebody sending e-mail to @mydomain.com , of course.
For that reason I run a whitelist.
E.g. block mail from *@mydomain.com EXCEPT for : addresses actually used@mydomain.com
This saves a lot of mucking about at the domain provider/e-mail provider's end (setting up either separate mailboxes or aliases), whilst giving you a theoretically unlimited number of e-mail addresses to use.
One word, though... postmaster@ is a domain that should always be reachable as declared in the RFXs. Thankfully I haven't seen much spam to it.
If you're running a business, then info@ abuse@ contact@ webmaster@ are likely to be mailed legitimately as well - though info@ certainly gets a good portion of spam.
And, lastly, it doesn't do anything for those making typoes in the e-mail address. Those having sent it that way assume it arrived properly.
This *could* be counteracted with a smarter filter that looks for potential typos, but I tend to think that the odds of that happening are so small (given that vitually all e-mail will reach you via link, copy-paste, or address book entry), that it's not worth the effort.
I used to run a qmail server for my personal domain. Qmail accepts mail first and asks questions later - that is to say, it doesn't reject invalid addresses during the SMTP session, it bounces them back later.
The result - thousands and thousands of spams to made up usernames.
I've patched qmail since then, but they keep coming in every day.
I have my own domains on a machine co-located at my ISP. In the past 4 months I've seen alot of spamming done by just sending to a list of common usernames @my domain. If you want to see such a list, they're great for building your own mail body check and header check bounce criteria. However, the down side is you will get many 10's of megabytes of this crap.
(I think the address to forward spam to is "uce@ftc.gov" I might be wrong though, rifle around on their site.)
You are so close to the right solution. Spam almost universally will have a spoofed address, so sending something back to the 'sender' will not net you any more spam. Sending back is OK.
The trick is to put useful info into the reply. Try setting up a message in the 'this address does not exist' autoreply. Put in something like 'bob@domain.com does not exist. If you are trying to reach Robert Smith, please resend to robert@domain.com. If you want to reach someone in an administrative capacity, send an e-mail to admin@domain.com'.
You can extend this to all the positions that matter, postmaster, webmaster etc, and a few key people at the domain. The bad guys shouldn't get it, and the poor twinks who have their domain name spoofed will probably ignore it.
The people who DO need to contact you and did either screw up or guess wrong will simply get the info that they need to do right. Win/Win.
-Charlie
I have my own domain and I disconnected the catch-all pretty quick.
Why?
Because there's no point in having it. You're either going to email me at my correct mailbox (which isn't too hard to remember - it's one letter long) or try and be a smart-ass (in which case, I don't want your crap anyway).
Think of it as an asshole-filter.
Accept email for the following accounts:
postmaster, abuse
and
hostmaster, security, noc
and optionally these:
usenet, news, webmaster, www, ftp, uucp
UUCP. Heh.
Read up on which addresses should be accepted by going to rfc-ignorant.org.
They have pointers to the relevant RFCs that specify necessary (RFC mandated)
addresses.
Accept email for your personal addresses.
EOL
Mistyped Emails: Let them bounce and let the correspondent eventually use the
correct address. Accepting random addresses on the off chance that
someone will use one by mistake is like packratting all that dusty
computer equipment. More resource intensive than actually valuable. Go
get that stuff recycled, btw.
Promote a few bogus, unlikely email addresses (e.g.
dmdxosmj843312@domain.tld) as spam traps by publishing them obscurely to
humans, but visibly to crawlers. (Small font in uninteresting web pages,
with disclaimer in mailing list messages, etc.) Use them as a feed to
train your filters.
Mandatory Domain Addresses: You just got the list.
Ad-Hoc Addresses: Use a different method to create temporary addresses.
Receiving emails to all addresses is not a temporary thing. At best you
can blacklist ones that get out of hand, but you really should be
whitelisting as needed.
I run a small hosting business, and by default, my accounts come with a catch-all that forwards to the admin account. I disable it on my personal domains, forwarding it to the site blackhole (basically /dev/null). I used to use it to get mail for a number of different names (info, sales, ect.), but it ended up saving me from quite a bit of spam to just alias those names instead.
If any of my customers ever complain about spam from the catch-all (and at this time, none have), I will tell them how to disable it in a heartbeat. I leave the decision to my customers, but really, catch-alls are pretty useless when I offer unlimited free aliases.
Even better might be to interpret all mail sent to the catch-all account as spam, and use it to train the filter for real accounts (though there might be issues with legitimate senders mis-typing account names).
-jim
If is much easier to have people tell us names and have us turn them on. It is just as easy for people to create a name "spam@whatever" and retire it when it gets nasty and start a new one "spam2@whatever"... which allows them to easily use email addresses at sites where they are required and discard them as they see fit.
We configure all our catchalls to issue NO SUCH USE reponses as well.
I once had my domain forwarding all my mail to my Yahoo account. Problem was, because its an old domain, and has been around since the mid 90's, I would get thousands of spam messages a day, before I filtered out any messages that weren't addressed to my user, or one of my valid aliases, way too many too look through, even quickly scrolling through.
/etc/aliases, and running your own email server. Then, you can just add aliases when needed, kill aliases that end up going to spammers, and pretty much have everything a catch-all address has, except you won't get the Joe Blow who typos your address with the message you desire to receive.
A good compromise is having a bunch of aliases in
I have written a tiny perl script to nuke the duplicates in my catch-all mailboxes and it has cut out 90% of the catch-all spam. In this day, a catch-all mail box to a domain that has been around a awhile will recieve between 5 to 7k e-mails per day (at least mine do) however the majority are shutgun style spam with same e-mail addressed to a dozen or so random names.
tmda
BoD
For example, if you want to register at example.com for something, you give them the address me.example@yourdomain.com (or some structure which has a prefix or postfix, the 'me.', and the site name for which you are registering).
What I've been doing for the last couple of years is using a catchall at a subdomain of my actual domain. The typical dictionary spams (postmaster, sales, etc) don't come in, because they only work on top level domains (otherwise spammers would be wasting a large amount of time spamming "sales@www.domain.com" which pretty much never exists..
When I sign up for an account at example.com, I just register as example.com@catch.mydomain.com. If I get spam, I can block it, and it doesn't interfere with my actual domain. If I decided one day I get too much spam to it, I could just switch to another subdomain name.
Speak before you think
As someone who has been using catchalls for more than 2 years, I feel it's worth it, couple with a good client-side spam filter (Thunderbird works for me). I use a slightly different scheme that works against spammers who typically target only the first-level domain (i.e., mydomain.*):
There's my main email for friends and family: me@mydomain.net
There's my secondary email for less important personal uses: me@mercury.mydomain.net
There's the catchall, *@mercury.mydomain.net, which I use to hand out customized addresses to commercial sites, both so I can easily sort the important ones (Airline discount emails, etc.), and so I can track any lying bastards that sell me out.
Thunderbird has rules corresponding to the above 3, and the rest of the catchall email goes into the catchall folder. If I'm expecting something, from a signup for example, I'll quickly check the catchall folder. Otherwise, I check it about once a day.
In general, I haven't had wildcard spam creep into mercury. I guess that's because spammers don't generally bother with wildcarding subdomains. Also, mercury doesn't do http, meaning it's not generally visible on the web.
One for close friends, associates, individuals and people who the address is sent to privately.
Yep, that works until one of your "close friends or associates" clicks on an email worm and the contents of his or her address book get blasted across the universe.
Or until they send this great joke to everyone they can think of, and they mistype one address and the entire cc: list goes to a spammer sitting on a typo-styled domain name with a catchall address.
The only bulletproof way to keep an email address private is never to use it. Kind of defeats the purpose though, doesn't it?
However, I've had my own domain for years and heartily recommend it. The up side by far outweighs the down side.
And the fact that anyone will be able to reach you for the rest of your life at that one e-mail address is a pleasant bonus you will reap rewards from in years to come. I've received a number of welcome e-mails from friends I haven't spoken to in years, but who just knew that they had to remember my name to contact me whenever they wanted.
-- My choice of computing platform is a symbol of my individuality and belief in personal freedom.
One thing we do as a company is use a catch all address from our hosting provider, pull all the mail down with POPBeamer for Exchange, filter the mail with GFI's MailEssentials and MailSecurity, then deliver the mail to the correct mailbox with the Administrator getting all mail not otherwise deliverable. If you want to provide internal mail for a couple of people in your home, this process may be worth it. Otherwise, use the mail accounts your provider gives you (ours gives us 10,000 with our $20 a month hosting plan) and skip the catch all.
Forget the "Catch All" e-mail address. Use Mailinator.
FYI -- mailinator is a non-passworded public catch-all system. Perfect for temporary site registrations. I use it frequently and its an unbelievably good service...
------ The best brain training is now totally free : )
Spambayes. Problem solved.
. . . and eventually I turned off the catch-all feature. It was very nice for about a year, until some spammer decided to start sending spams that appeared to originate from non-existent email addresses at my domain. Then all of a sudden I started receiving some four thousand messages per day to accounts that didn't exist. Most of them were bounce messages -- "Postmaster: error, user X doesn't exist" or "Postmaster: No such address" -- but there were also a few actual emails from incensed people demanding to know why I was sending out pornographic horse-on-girl crap. Oh, and one person wanted to know why on earth I wanted to sell her both breast enhancements and penis enlargement pills.
After a couple of days of that, I turned off the catch-all account. It's just not worth it.
From personal experience with my own domains, I have never ever gotten a legit piece of email to accounts other than real ones. I daily get emails to webmaster@[domain.com] and sales@[domain.com] (account that don't exist) and all are 100% spam, generally, of the "Does your business need a new logo?" variety.
From experience in operating multiple servers hosting many(read 10,000+) domains each, I can say that the catch all account is a VERY BAD thing.
Spammers recently have turned to more use of the random username approach and the catchall catches, well, all. This can in some cases total to more than 4500 emails a day in some cases. Hardly something you want to pull through a POP3 connection if your ISP doesn't have effective spam filtration.
Quite honestly the catch all serves little purpose if your email transactions are done in a correct manner. mailto: links have NO BUSINESS being on a web site for a company(or personal user for that matter) a simple CGI based contact form shields access from spam bots getting your email address and you can make sure ahead of time that your email address is properly configured.
Secondly, if you are emailing somebody else, most people use a context menu on the email you sent to add you to their address book. Again that eliminates the human error factor.
Also as others have already mentioned, a human will be able to read a mailer daemon response telling them that there was a mistake should they send directly.
My $0.02
SW
Make sure addresses like postmaster@ and abuse@ work. They're unlikely to get spammed, but may well receive important messages.
postmaster@ is actually required by rfc2821, btw.
As for the subject of the discussion; my catch-all addresses have been fine, but YMMV. If I was that worried about dictionary attacks, but still wanted the ability to give a new address out to each company, I'd do something like *-signup@mydomain or *@signup.mydomain or similar, but you might not have that level of control (in which case I'd recommend finding somewhere better to host your email, but *shrug*).
I guess the question is "What is the value of catch-all mail". If you are expecting customers to be clicking on a mailto: they will have the right address. If a friend replies to your email, they will have your correct address. If a person reads the address off of a mailing list or newgroup, they will have the right address. All of these situations are high value for you. You know the people, or you want the people to contact you. The only case where you lose out is when someone types your email address in incorrectly. Now how often does that happen, and what is the value lost? If you publish a newsgroup about leprechauns, and a complete stranger tries to send you their feelings about the little people, then you have really lost very little.
If your email includes orders for merchandise, and it is possible a person might have hand typed the email. It might be worth catching those, but again... "What is the value?" If you sell $500 stereos and find one order a month addressed to the wrong email, it might be worth your while. If you sell widgets at $2 and find one order a month go missing, searching through a pile of spam to find the treasured Order, is not worth your time.
Do you like dredging through spam in order to find meaningful emails? If you think it is fun to sit up late at night building rules for spam filters then go for it. If however you think the technology should be working for you to reduce the hours you spend dealing with administrivia, drop the folks who can't type? What would the logical extension of email-catchalls to the rest of the world be like... For phone numbers??? For letter mail??? For the serving of legal summons??? Yes, never in a million years (never say never) would we think it reasonable to receive 100s of other people's phone calls letter mail and legal summons(es?) just in order to also receive the people who didn't know our phone-number / address.
Email catch-alls really seem like a "Because we can" technology, rather than necessarily a good feature to have simply because it is included.
If you didn't feel like registering a domain name just to maintain your email address, you could always look to a provider who offers generic email pop3 email accounts at a reasonable price. Like one featuring spam Assassin and webmail with addresses ending in "emailonline.ca" from
GreenTree Software.
Greg.
"Sometimes you've got to kick at the darkness till it bleeds daylight" Bruce C0ckburn
If you have your own domain, the simplest thing is to use abuse@yourdomainhere.com. Someone posted this suggestion on slashdot a couple of years ago and it works great. I never receive any spam.
If you don't mind spending a few extra dollar a year for a domain, this is the way to go.
One of the options provided is to make one of your email accounts a catch-all account. In other words, any email sent to this domain with out a valid user name, will be dumped in the catch-all account. The question I have, is this a good idea or not?
Perhaps I don't know what I'm talking about but I think you should do something like this (now that you have a domain and hosting) . . .
Give people your web address instead of an email address and have your host deny email service to your domain except for those Addressed TO a single specific adderss. Next, configure an email-webForm with a CAPTCHA field. Users are asked to include their address and the text is sent via the form to your application(scripts). With no CatchAll in place you can deny all email EXCEPT to one specific, and preferably obscurly-named email address. With existing Trusted contacts and New webform contacts you can build a list of addresses which you will accept mail from and can give them THAT address. Now the lock is tight in both directions - all others need to knock at the front door before entering your bus.
Of course, I like to dream alot about taking down Yahoo!, Hotmail and GMail all within a couple of weeks of adoption of my new paradigm. And there was that talk of me being the Village Idiot. Thank God we lived just outside the city limits!
Stuff that matters.
on my website i add a whole bunch of fake email addresses similar to mine in alfabetical order, then in Mozilla Thunderbird, i set a filter that says if there is an email addressed to (similar email address here)x50 to mark it as spam
." all with mailto:___similar_email_address_here___ as the URL
so at the bottom of my site you see a whole bunch of hyperlinks, ". . . . . .
usually spammers seem to CC: or TO: email addresses close to your's, and usually send one domain at a time (by sending one domain at a time, it speeds up sending for them).
i think if you do something similar to what i do, you shouldn't have much of a problem.
it works pretty good, since using Mozilla Thunderbird i went from more than 100 spams a day to Zer0
As someone who runs a free POP3 e-mail service (www.nerdshack.com), I know exactly what it means to open up a catchall account (I don't have one). For about two months before my service went live, I had postfix up and running in an almost ready configuration. Over that time, my server averaged about 1000 rejections a day!
Why you ask? Well I figure it was because of two reasons. One "nerdshack.com" & "mailshack.com" are both easily guessable domain names. If the domain name had been, yoyoyoshackisaplace.ws then no program would have randomly tried that address. However the combination of an address (which is posted on the net a few places because nerdshack.com used to be an Inet BBS in San Fran back in the late 90's), and because its a simple word combination made me think it was getting guessed by spam bots.
The other suspect I have is reverse DNS. I know spammers poll random IP addresses looking for open port 25's. Well then you may ask how they guessed the domain name? Simple, once they have the IP, they just need to do a reverse DNS lookup. I think this was the biggest cause simply because our SMTP server was reversed to mail.nerdshack.com, and a good chunk (maybe 70%, but just a guess) would try using username@mail.nerdshack.com. That seems like a dead giveaway to me.
What can we learn from this? You will get more spam at a catchall address if you have an easily guessed domain name (or one that is linked to/posted on many websites). You will also get more spam if you have your reverse DNS setup correctly.
Whatever you do, make sure than you publish SPF information. The answer to all of the random@domain.tld scatter back spoken of above is to publish SPF information for your domain. Many sites use this information to make sure e-mail is not coming from a forged sender. This will at least stop those sites (many of the major e-mail providers) from bouncing messages into your e-mail box.
Of course DomainKeys are right around the corner, but they depend on a) implementations being availible (none for Postfix), and b) people using it. SPF on the other hand will work now, and a good chunk (20k domains at last check) enforce it. Check out (spf.pobox.com) for more informtion.
Now the reason I titled this post depends is because there might be a good reason to use a catch all.
Some friends of mine have a low traffic domain (www.raz[no I am not giving it out]ion.net), and they use a catch all to make sure all client e-mails make it through. They also do the requisite junk address for those mandatory registartion pages (thank you bugmenot.com). They find it useful to do the joe.ebay@domain.tld scheme because it becomes easy to make up, and filter e-mails.
Long term, just make sure you have a good spam filter. The one I reccomend is DSPAM (www.nuclearelephant.com/projects/dspam), though recieve fair warning that it is very difficult to implement. I ended just using their library (along with the ClamAV library) and wrote my own interface. (I hope to deploy this code in the next month or so, right now I use SpamAssssssasain).
Anyways, thats just my $.02.
I have a catch-all enabled that dumps into spamtrap@mydomain.com... I have root/postmaster/etc aliased to my real email address.. Whatever spamassassin doesnt tag as spam in the spamtrap accounts gets re-fed into the baysean filtering afer I skim it really quick to make sure nobody just mistyped something... Works really well..
Please mod the parent up. I have my own domain that comes with unlimited aliases and I use them for every account that I use online, e.g., if I shop at CDNow, my e-mail is cdnow at fatchuck dot com.
FWIW, I've never received a single spam to any aliases outside of my slashdot alias and I've got about 20-30 of them. Now, I bought my domain after it had previously lapsed, so when I first got it, I got a ton of spam to webmaster@, master@ and sales@. After going into CPanel and routing all e-mail for those addresses to the trash, spam has ended.
As the parent said, use wildcards and don't share your personal address with anyone besides very good friends and family, OR, make sure your personal address is one you don't mind changing.
Peace,
Chuck
I do this exact same thing (register on somewebsite.com as somewebsite@mydomain.com). It's great for tracking if someone gives out your e-mail, so that you can refuse to give them any more business at the very least. The mail all comes into my postmaster account.
If someone ever did give out one of those addresses. I would simply put a single rule in my filter and never see the spam again.
I've been doing this for about three years and have never had a problem with mass spam hitting the postmaster. Not once. I highly recommend it.
I use a catch-all account, but it is a separate account from my personal account (catch-all goes to null@domain.com). From there my mail filter (popfile) can automatically classify any mail that comes in the catch-all account as SPAM. So I get to use this free corpus of spam to train my filter without me actually having to do anything. For the family members who continually misstype my email, whitelists are used to make sure the mail gets safely through.
Bork Bork Bork!!
Catchalls are harmless until they explode. The results were not pretty. All it takes is to be targeted as a potential ISP goldmine of email accounts, and then be dictionary-attacked by a spammer, then lots of your email addresses are put on huge numbers of spam lists. Then you've moved from no spam to near infinite spam. Over one thousand spam per day, gobbling up your download bandwidth and slowing your Internet connection even if your spam filter filters 98% of it which still lets a couple dozen through, it becomes living hell!
/dev/random | mail myself@mydomain.com; done
while (true); do cat
...and I receive about 850 spams a day to addresses that have never existed.
Some of these addresses are obviously now on all the spam lists, and these addresses are responsible for about half of the spam. The other half are "dictionary" style attacks with addresses that use common names such as brooks@domain, murray@domain, jones@domain, etc. These spams often come in waves, but in general their proportion of the overall mix is increasing.
The irony is that I got the catch-all domain to help deal with the spam problem, but it has only made it worse. And the real irony is that none of the throwaway addresses I use to register for things have ever been spammed.
It allows you to have multiple identities and thus determine where spam comes from. Want to subscribe to a free registration website that requires a valid email address? It the site is yourfreepron.com log in as yourfreepron@yourdomain.com. Any suspicious messages in your inbox can be instantly associated with where it came from this way, and you still get all required messages from the website.
Paul Robinson <Postmaster@paul.washington.dc.us>
The lessons of history teach us - if they teach us anything - that nobody learns the lessons that history teaches us.
I own several domains and get surprisingly little spam from the catch all accounts.
I actually find catch alls usefull for the reverse reason... when I am forced to enter an email address I use thesite@mydomain.com... this way I can track who is selling/trading my email address. So for example if I use amazon@mydomain.com and 3 weeks later I start getting spam on that address I know where it came from. Also I can then set up that email address as a real pop address and never check it or better yet forward it to uce@ftc.gov the government spam reporting email address...
Someone actually does have the email address asdf@asdf.com. Here is his reasoning why he doesn't accept email to that address.
In soviet russia, You ask not what country do for you, but what you do for country!
Oh wait...
So I tried using a catch-all address one time for my domain. I left Outlook open all night and in the morning I had something like 5000 e-mails. So for me the very very small advantages (mistyped e-mails, etc) were far outweighed by having to go through all the spam not caught as such.
I run several domains where I have e-mail servers. Years ago I would forward the catchall to my main mailbox so I could see what was getting misaddressed and handle it appropriately, often forwarding it to the correct address if I could figure it out. Obviously that doesn't work nowadays. I've set some of my catchall defaults to reply with a failure message and delete the message. You know, "No such address here." Some other domains, where the traffic is heavier, are set to send catchall mail to the "Blackhole" AKA bit bucket. In most cases misaddressed mail to my domains gets the failure message and, if they really want to get through to me, they figure out what they did wrong and I eventually get the message.
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
I own two domains, both running catch-all. I do not get many spam mails on the "random" account, most of my spam is adressed to the address I use widespread in forums and stuff.
I think only 10-20% of my spam is recieved via the catch-alls, that would mean roughly 10-20 mails per day. I get about 100 spam mails per day. SpamAssassin doues a great job here, so I don't care much any more. It's just removed. The catch-alls are not really making it worse!
If you have 1000s of messages coming to a person computer it doesn't mean squat what your filtering scheme is. Even if you don't "see" these messages, you machine is still going to have to read messages to evaluate them, or at the least download the headers (though header analysis isn't going to get you 100% filtered spam )
Accepting email from 1000's of possible email addresess @ your domain when you know they're all bogus is just asking for punishment.
In my former life as a postmaster, I got a good look at what catch-all accounts do for people. It wasn't pretty.
:-)
Picture the scenario of a dictionary-attack spam: the catch-all box will accept *every* one of them. If the attack covers 50,000 potential addresses, well, you'd better have a large mailbox
Also, WRT important accounts like postmaster, that should never go to a catch-all account. See RFC 821/2821: the postmaster address must work, must accept all mail, and must be read by a human. You should explicitly activate postmaster and either read as postmaster or alias it to your real address. Don't let it get caught up in a catchall mess.
For other "important" accounts, they should exist only if you have that role. For example, if there is no website, don't have a webmaster account. It will just be a spam magnet. Ditto for admin, and any other common role accounts. The only one you are required by RFC to have is postmaster. Dispense with the rest. Anyone who wants to contact a role account and can't figure out to try postmaster is someone you don't really want to hear from anyway.
1.5 years, no dicitionary attacks.. catchall in place, and forwarded to my "main" email for the domain
I use per domain/individual emails, I told my local circuit city my email address was circuitcityac@mydomain.info and so on..
the only thing that sucks, is I can't find an email client that lets me generate replies using variable return to me email addresses created on the fly, I have to make an entire account for it to work..
what I do is edit my 'generic' info account before each email, where I don't want to give out 'me'
every day http://en.wikipedia.org/wiki/Special:Random
Personally I don't use wildcards for any of my domains. I do frequently make new aliases that I only use one or two times just to provide sites who require a valid mail account with something, after I get the confirmation mails I remove them. And guess what? Many of these temporary, now invalid aliases recieve spam attempts - spam I would get if I used wildcards.
:)
Personally I'd rather not get mail from people who are not smart enough to type my mail correctly...
9/11: Never forget it was a false-flag operation
I have been hosting several personal domains for years, all with a catch-all account. The spam I receive on most is minimal, mostly stuff promoting web related services. I guess that this is simply from people who crawl the domain names and send to basic accounts like "admin", "webmaster" and "postmaster." These can easily be identified and filtered.
One thing I have noticed, is that one of my domains is the one I use for web hosting. I have determined that if you have a domain with a website that is linked to throughout the web, you will receive a ton of dictionary email account spams. So, if you get your own domain, don't use it for a web hosting domain and your spam quantity will be quite reasonable.
Of the 5 domains that I own, only 1 gets lots of spam to the catch-all... that one is the domain with the web hosting. All the others are minimal.
Oh, one of the other benefits of a catch-all, is that when you are forced to include an email address for some web sign-up, you can invent an email address under your domain without setting up an account. So, if you sign up for a give away at www.freebeer.net, you use the email address freebeer.net@mydomain.com... you can then get the mandatory confirmation emails, but you can later filter that email address and track if that email has been sold. It is a beautiful thing. If the email gets sold, you simply start forwarding all the mail on that account to some email address at the original company that sold it.
just my $0.02,
"Perhaps most amazingly, votaries of 'diversity' insist on absolute conformity." -- Tony Snow
Why does email make it to my mailbox when it DOESN'T have my name in it in the first place?? Maybe if we fix that, we'll cut down on most of the spam.
http://www.sneakemail.com/ It's free, you can make as many addresses as you want, and when one starts getting spammed, just delete it. Use it for your own Web site; when it starts getting spam, delete the address, make a new one, and put the new one on your site.
http://www.fastmail.fm/Best e-mail provider, IMO. Their paid accounts can't be beat for price or features. Excellent uptime and service. I use them to host my own domain. Catchalls, custom server-side Sieve scripts, and several free aliases on their own domains too. Good SpamAssassin filtering too. You can try out a more limited free account too.
"Those who consume the bulk of goods are those who make them. We must never forget this secret of our prosperity."
So many people use things like:
johnNOSPAM@example.com
john@NOSPAMexample.com
johnREMOVETHIS@example.com...
that the SpamHarvest bots seem to harvest emails and then REMOVE words like:
SPAM
REMOVE
THIS
NOSPAM
before adding the names to their "fresh" list of email addresses to sell.
but if they remove SPAM from SPAM@example.com, they are left with.....
@example.com
which should be undeliverable.
so if your email is SPAM@example.com, you should get email from your friends, but my extensive use of that username on USENET has shown me that it does in fact work! I received only ONE spam email to that address in the past year of using it.
getting back On Topic for a minute, see if you can "disable" the "catchall" or "*" email function at some point. While I have not been hit with a dictionary attack, its obvious from the other posters that it is not uncommon. If you can route all non-assigned usernames to null when you discover this to be a problem, you will save yourself some headaches.
I like microcars
>... the poor twinks who have their domain name spoofed will probably ignore it.
This is *such* annoying advice. I have a long-duration (approximately 1993) very public email address, and it's spoofed a lot and one of my main annoyances is this auto-replied "You've reached a bogus address or domain" message.
DO NOT send any auto-replies for anything.
DO NOT send messages saying that the (probably spoofed) sender has sent you a virus.
... from nowhere.com
Please bid on this Karmann Ghia! Please pleas
I have a funny real-life name which is often misspelled, so I set up a catchall on my mail server to forward everything sent to my domain that doesn't quite match any of the addresses set there.
At first, yes, I did get a lot of spam. However, it's tapered off thanks to two things, I think: 1) Mail filtering on my end (I use SpamBayes and LOVE it to death), and 2) spammers gradually abandoning the tactic of mailbombing a server with any name they can generate at random.
I'm not so sure about #2, but I have been getting almost all my spam sent to a specific email address of mine that is public. Curiously, it is NOT the email that I used on my site to contact me with.
Sum of comment: I use it, and the spam problem hasn't stopped me from using it.
Honorary Member of Jackie Chan's Kung Fu Process Servers
I have more details in my Kuro5hin diary:
-
Two Thousand Spams a Day - mostly racist messages intended to affect the recent German elections
-
Four Hundred Megabytes of Spam a Day - mostly the zafi.b virus
You`ve got 1 VoiceMessage!My hosting service had the ClamAV antivirus software installed for a little bit, but had to disable it because it was using too much CPU time, I think because the host was getting so much mail.
Request your free CD of my piano music.
One argument: error messages tell the user that they didn't get you; if it goes into a mailbox with 10e3 other emails you'll miss it. The latter is a worse situation.
Another argument: you _will_ get tons of spam. I did a catch-all account on several of my domains when I was moving (basically, a friend of mine handled all my mail by passing everything addressed to one of my domains to a procmail script I wrote to handle it). My spam went up by about a factor of 5.
A counter-argument: I also found that if you assume that everything to an invalid address is spam, you have a pretty good source from which to train a Bayesian filter.
So it depends on what you want. If you want some Bayes fodder, go for it. If you're doing it for convenience, it's not going to be as great as you think.
It wasn't much of a problem for me, untill some spammer started faking address at my domain. Now I get tons of "message failed" emails. *sigh*.
That said, having a catch all address is actualy a great way to prevent spam. Why? Because whenever you're required to enter an email address, you can just make one up on the spot. That way, you can get the corrispondance you need, and if you ever get spammed on the address, you'll know who sent it. And you'll never have to worry about getting your primary account spammed.
autopr0n is like, down and stuff.
What I do, is give a different email address to everyone who asks for one, if one of them gets too pesky with spam, I SMTP reject it with a message directing them to a webpage with my new email address in a GIF file with a background that thwarts optical character recogniotion.
So far, I've rejected thousands of spam, but never got one spam hit on my GIF email address.
Also, so far I haven't had to block all address to prevent random email attacks, but it would be easy enough to block all and add a new email every time I give out an email address if I wanted to.
I've been running a catch-all for several years, I get an increasing number of dictionary attacks, other than that, works wonderful.
Started forwarding to a gmail account last month, opened up all the previously blocked addresses to test their spam filter. I average about 2 spam messages getting through per week, and don't have to worry about deactivating compromised addresses. Gotta love google...
I have managed a catch-all address a few years back, and found it to contain almost no spam, but our whole domain was rarely attacked back in those wild and woolly days. Catch-all + admin = forward to the right person in a timely manner.
/null and a bounce is generated back to the sender. Something more inteligent gets sent for human review.
/null and bounced back. Seeing as most spam is sent to a single e-mail, not multiple TO addresses, this would keep human-sent messages safe, but pick on spam mostly.
As for today's spam, what about a heuristic (sp?) based filter on the catch-all with a bounce message generator? If it is spam, the message is sent to
If that is impractical, what about this for a method to kill dictionary attacks: Check for matching message portions. Couldn't you just check if the xth through nth characters of body are the same (where x is a few lines in, to prevent DEAR {NAME-MAILMERGE} from spoiling a match), then the mail is a repeat, send to
Then again, these could be the ramblings of a madman with little programming experience. YMMV.
Rule of the open mind
People who are resistant to change cannot resist change for the worst.
I don't get so much generic spam to @mydomain.com but I do get tons of bounces from spam that's sent out with a spoofed from @mydomain.com
The man who trades freedom for security does not deserve nor will he ever receive either. - Benjamin Franklin
I've run mail servers for years and have, at times, thought the war on spam was a lost cause. I have taken these steps to reduce the spam. I do not use globals, or global email addresses of *@domain.com. They catch a lot of spam and then a lot of other stuff that you just don't need.
I also run and maintain a blacklist, sometimes incorrectly referred to as an RBL. RBL was the name of one such list, not all of them. With a simple web interface and a MySQL database behind it, our blacklist is kept up to date by the most ardent of our spam haters. They dilligently add the new IP addresses for any spam they receive. We went form blocking 10 to 20 emails a day from the blacklist to blocking 1000's in a matter of days.
In addition to our blacklist, our mail server runs on several other blacklists, such as spamcop and spamhaus lists. Beyond that, we also use a mail filtering program called spamassassin. This is just one of several out there available.
But, I'm getting away from the question. I have had bad experiences with global email addresses and can not, in good faith, recommend them. The best solution is to maintain your own mail server and configure it to fight the war on spam as best as you can. Running with an ISP solution limits what you can do. Setting up a global email address just sets you up for more spam. Putting an email address on a webpage just sets you up for more. If you have to publish an email address, make a second one and filter it in your email client, realizing that you will get bombarded with spam on it.
gpmac
I manage email for a domain that was recently "dictionaried" by someone who sent *15,000* emails, each with a different username, all to the same domain. My mail system was bogged down for a while trying to deliver the bounces, all of course to non-existant return addresses, which then bounced...and so on.
/dev/null.
I now have a catch-all setup on that domain, only it points to
There is but one valid reason for ever having a catch-all address. That reason is if you actually, honestly, truely WANT spam. "Who wants spam?"/I you say? I do. I have a handful of domains that have no other purpose in life but to collect spam. I've seeded addresses from those domains into dozens of spammers' "remove" forms. I built a list of 525,000 proper pronouns and used that to compile a list of userid@spamme-domains.tld addresses to seed those remove forms with. The end result is hundreds of thousands pieces of spam per day flowing into those domains. I archive much of it and automatically report the rest to the FTC as spam. Oh happy day. That's the only valid reason for ever using a catchall address that's publicly exposed to the Internet.
I run a friends-and-family hosting site (DNS, mail, web) for about 50 domains, almost all of which have catchall enabled. One user was getting 500+ spams a day, day in and day out. I was seeing 200-300 per day myself.
Four weeks ago I built the latest sendmail with Milter turned on and installed relaydelay.pl. The next day that user received two (2) emails, both of which were from friends. I got 7 emails, only one of which was spam.
Greylisting is the single most powerful anti-spam system out there. It blocks over 95+% of the spam and it doesn't "false positive" because it isn't doing pattern matches, Bayesian filtering or anything like that. It simply gives a TEMPFAIL to any email that has an unknown (from, to, server-IP) triple. If they come back more than X minutes later and less than Y minutes later, they are let through. Spammers almost always are using fire-and-forget SMTP servers so they don't retry, and so you never see their garbage. Positively elegant.
If you are the sysadmin, check it out and install it. Otherwise, hound your admin/ISP to install it. It saves bandwidth, aggravation, and time.
The corks just don't come out the way they used to.
-- My Wife, dealing with one of the new Corqs(tm)
There are a few ways to deal with the issue of spam if you've got your own domain. It sounds like you are at the mercy of whatever software is installed by your isp rather than running your own email server, and that's unfortunate because you could do more if you ran your own email server and dns.
I use qmail and djbdns for my email and dns. One nice feature of qmail is the dash-extension feature that allows you to setup email addresses of the form username-extension@domain.com. You can then give a unique email address to each company, organization, mailing list, etc. that you have to give an email address to. So, for example, when you order something for Amazon, give them the email address username-amazon@domain.com. The benefit is that if you start recieving spam at that address you know who sold the address.
Another tactic that's useful if you have the ability to easily create subdomains is to setup alias subdomains for your email. For example, username@subdomain.domain.com. The idea is to create subdomain names that reflect the fact that they expire at a regular interval. So if you gets lots of spam and need to expire the subdomain every month, call the subdomains jan04, feb04, mar04, etc. Use this tactic for mailing lists, usenet, and anyplace that you know can be easily harvested for email addresses. Once you expire the old subdomain the spammers can't even find your email server.
That's what you get for buying asdf.com.
-
Inventor of the term 'pardon my French'.
Not only do you get spam addressed to random accounts on that domain but all the Undeliverable Mail bounced back to spoofed addresses on that domain.
With my domain I have recieved 0 spam. 0 from the catch all. 0 from any valid email. I'm very happy with it right now lol :D.
I cut my spam back from about 500 messages a day down to 150 or so a day simply by turning off the catch-all sort of thing.
I still don't have it enabled on all of my domains, but on my main ones it helped a ton.
During the time that I had the catch-all working, I never once saw a real message come through, and saw an absolute ton of spam.
The only reason worth keeping it that way is if you want to see accidental e-mails - like where someone from AOL e-mails you and clearly thinks you are someone else.
But I would say those times aren't really worth it in the end.
There are some odd things afoot now, in the Villa Straylight.
If, as you say, virtually all spam has spoofed return addresses (And you are correct) exactly what will you accomplish by auto sending a reply to an innocent persons address?!?!?
No person and no admin in their right mind should EVER auto-send return mail to spam. You are mearley doubling the spam traffic! I get more idiotic returned mail to my mailbox because of F*cking spammers using my address to spoof with than I do spam itself!.
It's time that admins and individuals wise up and STOP replying to spam completely (Or any non-existant user name). Email traffic will drop by half on that fateful day...
Whenever I sign up to a web site, or give my email address away to a company or mailing list, I almost always give an address of the form:
[name-of-company]@mydomain.com
For example, slashdot-at-keithtyler.com.
Then, if that email address turns out to be sold or used for spam purposes, I can block that source very reliably just by filtering out that particular inbound address.
I also have a semi-robust procmail recipe that adds the first part of the email address to the subject, for easy detection:
Terrorists can attack freedom, but only Congress can destroy it.
"Perhaps I don't know what I'm talking about "
Being a little hard on yourself, that really isn't a bad idea. It does require a bit much from people trying to reach me, though. But.. if it ever got that bad, I'd seriously be considering it.
What I do today is encourage people to use ICQ instead of email. I get 0 spam on ICQ because it has a strict white list on it. The additional benefit is that it encourages people to keep it brief. I don't have everybody on board with that, but it has single handedly made me not so email dependent.
"Derp de derp."
I'm currently catch-all for ten domains. Recently my spam load has increased exponentially. It went from 400/day to 4000/day in the last six months, and I wouldn't be surprised if it doubles in another week or two.
In short, if you don't have a very effective spam filter, don't do it.
The Web is like Usenet, but
the elephants are untrained.
I agree that a catchall can cause problems down the road as you've described, but in this case the mail server (and bandwidth) are being maintained by someone else. Not to be cruel, but if the system admins allow catchall mailboxes to be hosted on their servers then they deserve all the traffic they get.
Of course if the user is pulling all the email down via POP3 then the bandwidth issue will hit home, and hit the hosting company twice.
"We make our world significant by the courage of our questions and by the depth of our answers." Carl Sagan
I love having a catch-all email account, and not much spam gets through my filter. My friends know I have a catch-all and often email me at frivolous email addresses like iwantmysweaterback@mydomain.com or cyndilauper@mydomain.com. I also like the ability to track which companies give away my email address by supplying each company with an address like spambites_idMicrosoft@mydomain.com. I also can sign my emails a variety of different ways (ben@, schak@, bs@, or b@mydomain.com).
Having a catch-all account forward to my main account on my domain has worked for years. Everytime i sign up for something online i give them a new email address made up on the fly (for example slashdot@wazer.net). Then when I get mass spamming sent to slashdot@wazer.net I know who broke their privacy agreement ;-)
Then you can simply block your OWN address that you gave away, and you have effectively stopped that whole stem of spam, regardless of the many people who send it! :-)
Get yourself some kind of protection from dictionary spammers, or you'll find your catch all one morning with 200,000 messages and counting by the second.
Also, while it's nice to be able to hand out any email address you want to sites, to see where spam comes from, the moment you get lazy... you end up with spam and you can't recall where you first handed out the address.
Make sure you have a blacklist feature on hand to quickly add addresses that end up spamming.
I get 3000 spams/day with my catchall address (krellan.com)!
I will soon be putting in a whitelist of allowed usernames, and bouncing everything else, in hopes of reducing this ridiculously high spamcount.
I get only 100 spams/day correctly addressed to my real addresses that I use on that domain.
This is still too high, but a combination of SpamAssassin on the server and Bayesian filtering on the client (Mozilla Thunderbird) help reduce the number of spams I actually see to almost none! (For safety and in case of false positives, all emails are still archived.)
Dr. Demento On The 'Net!
If you're not bouncing mail that landed in the catchall address, you are not being used as a "bounce relay" for that mail.
OTOH, if you reject that mail to the (forged by virus) sender, there is a chance the non-sender will open it and become infected with the virus.
Using a catchall makes it harder for real senders to find out why their mail to you is falling in a black hole, but it's still the responsible thing to do.
Help stamp out iliturcy.
The mail system I manage gets 30 GB per month of non-valid e-mail address spam. They originally had it set up on Exchange, but that server puts non-deliverables into a Bad Mail directory. Puts a quick hurting on a server. Now that I set up postfix on a secure mail relay, the number of non-valid address messages is no longer a problem.
My advice -- don't do it. But, it's your domain and if it gets targeted, have fun trying to manage that mail box, let alone deal with your hosting company.
Many people have been saying how they make custom addresses when they sign up for things so they know who spams them and can filter it.
You can do this in Gmail by adding a + to the address, eg someone@gmail.com can also use someone+list@gmail.com, someone+spamme@gmail.com etc. Then you can filter the messages based on the address it was sent too.
I am surprised they dont tell you about this, it is pretty useful!
mod parent up
for the domains I own, but the ISP I use has postini setup and available. It's nice to be able to give each "registration required" web site a unique email address to see who is betraying their privacy statement. On the other hand my postini quarantined list grows by about 1000 per day making it almost impossible to search through it for real emails. :(
"Who hasn't slipped into the break room for a quick nibble on a love Newton before?" - Mr. Peterman.
I do it mainly to see what websites are spamming me. For example, when I subscribe to the NYTimes, I would subscribe using nytimes071704@mydomain.com and could then see what advertising and spam comes from that signup. (If I get tired of mails to an address, I will make a rule so that all mail to that address goes straight to my trash).
My domains are not popular so I rarely get spam to emails that I never signed up anything for. Occasionally I will get an email to webmaster@mydomain or info@mydomain, but nothing more than a dozen a week. I say use it until you get too much spam, and then you can drop it while activating the emails that you still want to keep.
I use sneakemail to have unique addresses with a label for where I used it. All the addresses point to my main one so it's easy to tell when someone sells an address. then I just kill that address and no more spam.
-- "Freedom is the right of all sentient beings" -Optimus Prime
I had the full catch-all enabled for a while and it worked fine, until some spammer in Brasil started sending me hundreds of thousands of spams a week. It got so bad when I was processing with SpamAssassin on the hosting service's server that spamd dumped core and the provider closed my account for a time; and processing using spamd locally got to be too big a processor drain at home, too. So now anything that doesn't come to knownusername-*@mydomain.tld gets sent directly to /dev/null.
That doesn't eliminate every spam, but it's cut the volume of garbage that I actually have to download and process here at the house way, way down to just a few hundred a week.
Any other way and I'm simply overrun.
Remove the caps and hold to a mirror.
It works as long as you have some flexibility with configuring. I can manage my domain on-line and have done this: first I specified a forward address for ALL received email. Then I created 5 rules for specific email names to forward to a second real address. The latter I check continuously. The first one occaisionally - just to make sure it catches nothing important. I get 100odd mails on the first address daily and at this stage only non-spam at the second. In case one of the good addresses starts getting spammed, I would simply eliminate it from the forwarding rules and replace it with a new one. Another trick that I have recently implemented is to have the spam-forward address configured to auto-reply with a suggestion to look at a webpage which displays a jpeg (!!!) of a valid address - to enable a human email poster to pick up a working address - this is a 'redundant' address (mail123@domain.com) just in case the robots get clever!
Doesn't the RFC say that any message which is not delivered should bounce?
My personal experience: I had a catchall account for years. I finally dropped it because it, over time, became a significant contributor to my spam load.
Thanks ~ I'll let you know if I cross the chasm and make the big bread, loaf.
I used ICQ in '98 or '99 but it never took off for me. I like the idea of the whitelist and diskspace being maintained by the vendor and Not On My Machine. I saw IRC and ICQ as the same as Yahoo! Chat with the added dimension that messages could goto PDA, cellphone and kiosk - more of a salesman or CEO method of communication. I've blown through so many email accounts i can't think up anymore nics, let alone passwords.
As for Yahoo! they're using their bandwidth and diskspace to give me more tasks to perform(Bulk email) so that I have to view more advertisers. All this bandwidth and money changes hands over nothing - wild west indeed. Just a medicine show. It's a microcosm of the vicious circle we see when middleware and bloatware push us to purchase newer PCs.
Before Time, I remember the local BBS guy used to only relay email on Saturday mornings around 2:30am because the next node on FidoNet was long distance AND 200k of weekly email was a major resource event! But we survived and we liked it that way. So was born: "Less is more."
Stuff that matters.
I just use bogususer@chez-vrolet.net and let my MTA tell them that I don't exist on usenet. =^_^=
This sig no verb.
I've been using a catch-all for years now, and used to love it. Whenever I'd give a e-mail out, it would be company@xxdomainxx.com (so, like, slashdot@xxdomainxx.com) This would let me track companies that sell the e-mail (so I could grip at them - not that it does much good) and turn the e-mail "off".
The problem is, the last year or so, I've been getting randomname@xxdomainxx.com (like john, ralph, fred, at al). Four months ago I was getting 1500 spam to random names. Today I'm hitting about 4900. My spam filter works fairly well, but if it misses even %10, that's a a LOT of spam to deal with - and it usally gets 20-30%.
So, I've essentially turned off the catch-all (still getting it for a while, as I have to change the hundreds of e-mails I've sent out over the years), but the catch-all doesn't go to my main e-mail, it goes to alt on - that ends up in a folder that I go into every now and then (that folder currently has 62k messages - about 99% of them will probably be spam).
-Greg
First, I just want to respond to some of the earlier comments that recommend not using a catch-all and instead bouncing back a reply when emails are sent to the wrong address. This is a bad idea. Don't contribute to the quantity of unwanted emails clogging up everyone's bandwidth.
::blackhole:: the email, or actually collect it through a catch all address. Don't send a response.
I guarantee that, regardless of the amount of spam involved, you will receive more spam in your catch-all email address than genuine-yet-misdirected emails. And since spam is frequently sent with some unrelated poor individual's email address tacked on in the 'from' and 'reply-to' headers, you're just generating more unwanted email for these folks. If somebody really needs to get ahold of you, and they don't hear a response to their email, they'll either try to send it again or try to contact you via different means. Either
Now, in my own experience --
I run a handful of domains. I operate my business through email, so it's doubly important for me to archive all communication. I do throw all email received from my catch-all address directly into the trash (and some of my catch-all addresses get several hundred pieces of spam every day). But I only throw out my spam once a month or two. So if a client later contacts me, asking if I received his email, I can at least search for it and retrieve it. I know it might seem pointless if I can just get the information from them again, but my clients for some reason like it better when I can find an email they've sent than to discover that it was lost along the way.
It's also worth noting that people are understanding about spam -- I've never had a client get upset about their email being thrown out accidentally.
Punctanym: alternate spelling of words using punctuation or numerals in place of some or all of its letters; see 'leet'
I registered my domain around 1998-1999 and I used the "catchall" system for a long time. When I maintained my own email server, I would blackhole specific "TO" addresses, e.g. back in the day I had "Slashdot@...." as my email address, shown publicly here on Slashdot. I started getting truckloads of spam to that address, so I configured the server to deny any mail to slashdot@... (with a handy "Die in hell Spammer" message). (Spam is still sent to that address even though I haven't listed it anywhere in close to 5 years, and it hasn't worked in as long).
However I ended up having to stop running my own server, and got shared hosting, which has the "catchall" option for email addresses, but doesn't allow the blackholing of specific addresses. So I received the occasional spam, but it was pretty easy to deal with. But one day like 3 months ago I started getting buckets and buckets of spam sent by spammers who were sending emails to abc@... def@... bob@... sue@... etc. 200 a day was not uncommon. So I ended up canceling the "catchall" address and adding specific aliases for addresses I wanted to keep.
Basically the catchall is super handy, and I would love to be able to use it, but you will be opening yourself up to tons of spam. If I'm ever in the position to setup my own mail server again I will definitely do it.
rooooar
When I purchase something, I use @mydomain.com. This let's me track if they begin sending me spam or selling my address to someone who does.
For instance, let's say I buy something at Office Depot online. For my email address I enter officedepot@mydomain.com. If I start getting spam at that address, I know it's from them and can act accordingly.
I even had one company phone me thinking I'd screwed up entering my email address. Once I explained "why" I did that, they thought it was a really good idea.
I can't take credit for it though, I got the idea from my internet hosting company www.3-95.com.
My Tech Posts on Twitter
Just to fill in some details. This is a personal domain, and I am getting my email hosting from godaddy. I have decided to turn on the catchall feature. I created an email account called "catchall" and set it to catch all (Wasn't that clever). Within the catchall email settings, I put the Spam options up high. I did not consider using the catchall for instant email creation for purchasing, registration, etc. To comply with the standard Internet rules, I created a seperate postmaster and abuse email addresses. I'll go with this configuration for a while and see how the Spam flows.
Thanks,
Wildzeke
if you fill in an online for as CompanyName.com@domain.com, you can watch and see fi they sell your email address.
I have my exim configured to redirect any address that starts with fc_ to me, but ditch the rest.
That way I can make up addresses at my leisure, but don't have to let through all the crap to random addresses (which I was getting tons of, to the weirdest names!)
-- Only unbalanced people can tip the scales.
I got fed up near the beginning of this month when I realized I'd downloaded 3900 spams in just 7 days. I was using catch-all rather than just setup the addresses that I actually use. I turned off the catch-all and my spam decreased. Catch-all is convenient and it's a shame that spamming doesn't allow me to use it.
works for most however some business clients found that some former employee emails did not get any usable email - one former employee had nothing but spam and porn emails so in this case we jsut created email box called "dumpbox" and forwarded all mail for former and now more than annoying email addresses to it which were then routinely erased on the server. Worked well in the few instances where it was needed.
yes, better would be spam filter but if one or two addresses get nothing but porn and other unwanted emails why waste the resources processing the crap.
not being able to find my important letters because they are stuffed between pages of coupons and advertisements.
Wasting my time sorting through it all.
Spending even more money on trashbags to contain it all.
Worrying about getting package bombs, toxic chemicals, etc.
Getting very offensive messages from advertisers.
About the last one, I got a snail message that was addressed to my deceased grandfather. I politely sent a message back to them and wrote on it *hisname* died. Rather than stop sending me mail, they now send me mail that says "*hisname* died" as the addressee. It is in the least, very disheartening to be reminded of my grandfathers death every time I read the mail.
One day I'm going to run a dang gas line right into my freakin mailbox and set it to fire up like a torch at night. I'll put it on a swivel mount so every once in a while I can just tilt it over and dump all the junk mail ashes into the street.
Here are my top 100 in order of decreasing frequency, for what it's worth (these are all generic, I've removed a few specific to my domain). Together these account for about 75% of all my spam:
hanson greene gregory dean vargas hawkins graham elliott hardy graves ferguson hart harper guzman fletcher hale dunn haynes hammond day howell hamilton gordon douglas dixon vaughn garrett flowers duncan gilbert barnett walters fleming warren wade horton adkins watts sutton knight austin wallace barker banks armstrong andrews carroll watkins pearson johnston jennings cobb carpenter terry jensen peters palmer kelley stone silva santiago rhodes morales jimenez craig bradley soto malone hunt chambers burns sullivan kennedy hudson black sims pena olson may bush shaw ramos mills castro burke bishop snyder shelton powers reyes ray perkins schultz moody meyer page lucas miles mcdaniel
All people on my ISP get catch-all email to a "personal domain". It seems pretty harmless to me. Most spam is correctly adressed. I assume that's because random probes are inefficient next to address spidering.
Regardless, my Bayesian filter munches up 99.9% of it anyhow. Spam is basically a solved problem for me.
I work at a hosting company. Thousands of servers. Even more clients. The dumb ones all setup catchalls. The really dumb ones setup catchalls and vacation messages.
Catchall's are not worth the SPAM. Think about it, don't your customers and friends know how to contact you? If not, then you better do a better marketing job. A catchall is only good for SPAM, or when the system sucks too much and it just can't handle an email alias or 50.
I had a catchall going for spywareinfo.com so that I could make up an email address on the spot. netflix@, paypal@, pcpitstop@, etc.
/dev/null.
Earlier this year, several different spammers and viruses started dictionary attacking the domain. After three months of 3,000+ spam and viruses a day, I finally gave up. I turned off the catch all, bought a new domain which is parked (no content and no one's ever heard of it) and turned on the catchall there. I have a dozen or so dedicated web servers, so I just pointed mail.newdomain.com to one of them. The accounts that I actively used at @spywareinfo.com now forward to the new domain and everything else goes to
I have three addresses@spywareinfo.com that I can't turn off and an amazing amount of spam still comes to them, but not one spam has ever hit the new domain and I don't expect any to do so. I've started chaining Thunderbird to K9, both of which have bayesian filtering, and together they catch damned near every spam that comes through on the old addresses.
Only on
I have my email set to catchall and it doesn't seem to be much of a problem. However, I did seem to get a lot of spam set to sales@[my domain].com and webmaster@[my domain].com. So if you do have it set as a catchall I would suggest fowarding mail that is sent to webmaster@ or sales@ to me@privacy.net.
http://www.archive.org/details/ThePowerOfNightmares
Just discard duplicate messages and it will be like having one account.
I am looking for a solution.
Has anyone else seen this?
I vote no on a mail account that gets all email sent to the domain. I host a bunch of domains. When I started in '96, this was not a problem. Unfortunately, times have changed!
About a month ago three of the domains I host started getting LOTS of email. examination of the email showed that I was getting over 50K messages addressed to random names.
50K messages is a lot for me. A year ago I received 25K/week, and 60% were marked as spam by spamassassin.
Back to this year...Since no more than 25 of the current spam comes from the same host, they are impossible to block. That means somthing like more than 2000 comprimised machines sending spam!
I use Qmail...great software, but unfortunately it accepts the email before verifying that it can be delivered...then generates a bounce message. 25K bounce messages in the queue ties up a machine! At the moment, for those domains, I put all the email to bad accounts into the bit bucket. I will fix this next week.
Spam is expensive. I offer email free because it did not used to cost anything, but times have changed. We are talking somthing like 500MB/day...thats 15 gigs a month! Bandwidth cost money.
Filtering for virii and spam cost resources. 18 months ago 80 domains ran fine on a 200MHZ machine with 128MB ram. This month I replace that machine for the second time with a 2.5Ghz machine and 1 Gig of ram.
Unfortunately what is needed is for the ISP at one or more of these spam hosts to snif the traffic to the machine so we can find the source...this is not likely to happen!
These three domains have only 2 or 3 valid users each!
Any suggestions?
Mod up the parent comment, and shove a broomstick up my ass also
I just have to ask... why the hell did this get posted?
Try it, and if you get too much spam, disable it. Jesus.
autopr0n is like, down and stuff.
An alternative solution is the excellent SpamGourmet (http://www.spamgourmet.com) which specializes in moving email to /dev/null. You sign up for a free account and then each time you have to hand out an email address you give something like this: ..@spamgourmet.com
SpamGourmet will forward incoming emails on this address to your real address, decreasing the count by 1. Once it reaches 0 all future emails to this address will be dropped.
Highly recommended (and did I say it's free?).
Heiko
I run an Exchange mailserver for a very old domain, and have been debating the best way to handle the junk mail we get for several days.
A catch-all is out of the question due to the insane number of messages sent to random recipients @mydomain.com. I've also turned off delivery reports for incoming mail, as well as disabled receiving mail for anybody who's not in Active Directory. This, in conjunction with our spam filter seems to work fairly well, but we still get hit by a ton of spam each day.
What are some good practices for a domain like this? Any other Exchange admins have ideas about how to handle this? I'm trying to walk the fine line between being user-friendly so idiots can still send us mail, but also keep my users from receiving over 1000 spam messages each day. I'm also trying to avoid violating RFC, but it almost seems that things have changed enough since it was written that either it or the email standard itself needs to be modified as has been suggested by a number of big players in the field.
Ideas?
"What do you despise? By this are you truly known." --Princess Irulan, Manual of Muad'Dib
/)
One of the domains we process mail for gets > 100k bogus RCPTs a day. At the peak of this 6 month old dictionary attack, it reached 1.5M per day. Thunderbird is good, but that may take a while to download and process.
This is exactly why services like MailSift.com and Postini.com exist.
I own the domain of my last name, for example jones.com. Most spammers guess that a catchall will be placed upon that root domain. However, I create an MX record for my full name, john.jones.com, and then do a catchall of (at)john.jones.com pointing to my account. Spammers seem less aware (zero guesses so far) of MX domains. Then, wherever I have to give out my email address for a registration, I give a "unique" address used just for that site, such as slashdot(at)john.jones.com. This way, if any one address becomes abused, I just put a nouser entry in virtusertable for that address.
;-P . That would really reduce the effectiveness of this method as spammers would catch on. In which case, unique addresses would have to be explicit (many aliases) as opposed to implicit (via catchall). Slightly more time consuming.
I just hope this doesn't catch on too well
I am MuchTall
There are several worms out there that target random addresses in domains. One of my client's domains is under attack right now - over the past week, several hundred infected systems have tried to contact several THOUSAND different email addresses within this domain, which has 10 total VALID addresses. A catch-all address would simply put all of those copies into a mailbox somewhere...
I want to hear about it...
My biggest complain is that users who get ANY smtp error either ignore them, or assume the domain is down(i.e. server-type error) when the most common errors in my setup are user-type errors(user sent a virus and got a bounce, user mispelt an email address, user sent mail to someone over quota...).
I wonder how much can be blamed on email clients meant to curry favor with users who don't want to bother with fine distinctions(some email clients who assume users CAN learn how to use computers, unfortunately they are the minority) and how much is compatibility with legacy/non-smtp email systems, and those people coming from custom setups(aol/compuserve) that would be an interesting research for someone who's bored I'm sure.
I add a couple of extra spamassassin points to Emails that are not addressed to one of my published addresses.
However, there is another domain which has had banner ads for its services. After getting a particularly bad spam attack (around 30k/day to random addresses @ that domain from the same spammer), I spoke with the owner about killing wildcard handling and instead only handling the ones being used.
Btw, three months later, that spammer is *still* being hosted by CW/Savvis. http://www.sheckmedia.com/ is the site of the spam domain owner, but the spamming subnnets, 64.70.43.0/24 and 216.39.64.0/24 are different than the website. Anyway, talk about bulletproof hosting...
After setting up individual boxes for that domain, I decided to direct the rest into a file just to see what kind of crap comes through. For the month of June, there were over 107000 emails. For the month of July there have been 41969 so far. The July numbers are probably a bit lower because I recently added njabl.org blocking (w/o dialup blacklisting) with rbldns. During both months, spamhaus.org's lists and spamcop.net's lists were in use.
So, it's not really a matter of whether or not you handle wildcard addresses, but whether the spammers to decide to use dictionary attacks on your domain.
I've used a webhost called Dreamhost.com for a few websites, due to the problem with processing mail for catch all boxes, they stopped automatically setting up accounts with them. I believe that on their server the mail is just bouced if the recipient is not an available account.
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
Hell no! Don't do it! I recently wrote to my ISP when the spam email I got jumped from 900 per day to 5000 per day! It was WAY out of control.
What happened was some a**h*** spammer decided to apply a list of the most common user names to my domain. It took over an hour, over broadband, to munch through all those damn spams. And then the jack*ss sold that list to some other spammers.
Oh, man was I steamed.
So now I have a set up where I can specify the valid email boxes myself by putting a zero-length file in my top directory. Anything else gets zapped before it hits my email account by the ISP email server. And that's great, because having full control and flexibility over your email is what you're really trying for when you get a catch-all, but in today's world the spammers just make it impossible to enjoy that flexibility.
*** *** You're just jealous 'cause the voices talk to me... ***
use a free service like gMail untill they all get spammed then moveto another free uncomon service like...chabad.info....
Argh. They're talking about SMTP replies, such as 550 Requested action not taken: mailbox unavailable. Those failure codes can have a message that is shown to the sender in the process of trying to send. The rejecting mail server does not generate an email of any kind.
My catchall gets over 2,000 spams a day, mostly from cretins on fishing expeditions for valid accounts.
I personally like the catch-all. It is not too bad after I run it all through spam filters and personal filters. I like it too because it thwarts the spammers' ability to know good from bad addresses. And, I can find out who is giving away my address by using different accounts, like classmates@totallygeek.com, slashdot@totallygeek.com, etc.
Click here or here.
Believe me, that domain's mail is the worst spammed mother out there. But, I have had it posted all over for so long, there is really no way now to curtail the influx of mail. I have other accounts that are far quieter and I make sure those are not really out there.
Click here or here.
Here, here. Very well put.
I have my own domain with a catchall address. Surprisingly (or not), the vast majority of my spam is sent to actual addresses that I had posted on the website, signed up for a service with, posted on usenet, etc. at one time or another.
The biggest bonus for me of a catchall is that I now use a different address for each service, usenet posting, etc. I use. For example, if I signed up an account at crazycrap.com, I would use the address Me_CrazyCrap@myhappydomain.com. That way, for the email that IS sent to a legitimate address and not BCC'ed, I know exactly which site has sold out my address (or put it in a searchable place). Also, I can then block that individual address so that even the catchall doesn't receive it.
Unfortunately, I had originally posted on usenet a bit with my "main" address, and it remains riddled with spam until I decide to change it.
-- I prefer the term "karma escort."
BTW. Unlike phone numbers, I think you will find that most postal systems still quite error tollerant. If I sent something Calafornea, USA, it would still probably get there.
As for getting facts straight. Ever found it hard to read someone else's writting? Encountered a typo? Missheard someone? Not sure how to spell a name you've heard? There are many reasons for not getting the right info. Has nothing to do with stupidity or laziness.
We have a catchall e-mail address. We started receiving messages saying an outgoing e-mail was bounced. The surprise was that the originating user account did not exist! Apparently somebody was using our server to send out e-mail, maybe spam, from a fake account. A catch-all address can be useful in surprising ways.
I bought a bunch of domains and forward the catchalls to an email I monitor; I've had them for years and haven't had any problems with randomized user names (other than the ever popular info@domain.com) but have had problems with specific user emails getting burned. If your email pops up in a google search, there's a pretty good chance a spammer has it on a disk somewhere.
If I started getting randomized user names, I'd probably alias the catchall to me@privacy.net so that legitimate users would know that their email didn't get through.
A swift application of clue, involving a clue-insertion mandrel and Citroen Special Tool FBH-14, and it was all sorted out.
The only real advantage of a catch-all, like you said, is to catch mistyped emails which were intended for you but wouldn't normally reach you.
Your ISP should allow you to set up a number (usually unlimited) of free aliases for your email account.
So, if you are joe@domain.com, you could create a number of aliases that redirect email to your mail account, transparent to the sender:
joesmith@domain.com
jsmith@domain.com
joes@domain.com
joe.smith@domain.com
j.smith@domain.com
etc
As someone else suggested, it's also useful to sign up with websites with "personalized" emails based on their name... like signing up with NYTimes as nytimes@yourdomain.com. Then, alias that new address back to your name.. and turn it off if they start spamming you.
-David
Don't use the catchall, but do create some aliases of common misspellings of your name, or common combinations for email addresses, especially those aliases which you have used before with other providers. Furthermore, if someone really does not understand what to type, you can always send them a mail first, and then ask to reply.
Having done the same thing before, I can say that without a doubt, it will increase your spam.
The thing is that alot of spammers seem to literally shotgun a domain with information harvested, then use those plausible usernames as email addresses. The end result is that your primary email account will get flooded with email not originally destined for it.
If you do intend to do this, I would suggest the following:
Having these on when you check and go through your mail will cause an increase of spam above what you are getting.
Best bet, have the domain name. Use one address, then close it and switch to another, within the domain. Have the original address just junk any future mails it gets once you are sure people have moved to your new address.
Seriously, it's just not a good idea.
Winged Power Photography
In fact, here's a helpful article I wrote describing how to eliminate six nines of all your incoming spam permanently, in a way that is impossible for spammers to circumvent without reading your mind and hacking every person you ever sent email to.
Spam Free At Last
I setup a catch-all account and use this ability all the time. For example I'll use slashdot.org@mydomain.com or site_i_know_will_spam_me.com@mydomain.com.
If you have any problems just block email sent to that addy.
Make sure you send your mail as outgoing@mydomain.com otherwise any mailing lists you write to will probably get your REAL email address out on the web and that's just bad news.
Do not make a catch-all. You will regret it. After someone used my domain as a spoof reply-to in several SPAMs, I started getting SPAM to all those addresses. When it got to the point of downloading 2,000+ a day (takes days to download on dial-up) I was ready to pull my hair out and start changing email addresses on all my accounts I have everywhere. Then, with no help from my webhost I managed to get those mails directed to another non-existant account.
I control several domain names.
:)
In my experience, you need to block sales@, info@ and webmaster@. After that, most of the email (and spam) will be coming to the single @ wich you are actually using. There will be occasional bounces to random usernames (from spam spoofing from: addresses), but not very many in my experience.
By the way there is no spam to unpublished postmaster@ addresses, probably because this is not an address spammers want to irritate
Some other users have complained that they got under a dictionary attack like you describe. But not me.
17779 eligible voters in a district, 17779 'vote' as one. This is Russia.
I mean look at it this way, if the spammer sends email to Josh@mydomain.com, or this_is_a_catch_all@mydomain.com... it doesn't really matter, if it gets to my inbox, it doesn't matter what email it was sent to! Amd its not like spammers are going to put each possible random combination email on the spam list... I mean they are not going to put 1@mydomain.com, 2@mydomain.com.. etc, by just guessing! If they have your email, you are going to get spam. I dont think it will make much different wether you have a catch-all or not. Just my opinion....
_____
Josh Powell - www.ki4bbo.org
This is a bad idea and generally not thought well of for specifically the reasons you mentioned in your "Ask Slashdot" article.
I wouldn't recommend it.
we have a proxy server that collects email from a pop3 server and distributes it among the users
If you have nothing useful to say post as AC.
Keep your life simple. Use email as an IQ test. If they can't get your email address correct or you can't provide links on web pages, then there shouldn't be any email communication between you and them.
Put it into perspective: Would you like to have a dummy phone number to catch all the incorrectly dialed phone numbers in your area code and send them to your home 24 x 7? You're basically asking for the same thing only with email.
If you make catch-all, make sure you block spammers in mailserver rules. It's very easy though, just put hotmail and aol on complete bounce and 75% of your spam is already gone.
Set up a catch-all account, but just have it send an auto-response - you don't actually keep the mails. They go straight into /dev/null.
:-)
The auto-responder then directs anyone who really wants to contact you to a web-page with a form on it allowing them request you contact them. Letting you choose whether or not to write back to their contact request puts you in charge, and if you suspect replying to them will put your address on a spam list, you can just delete their email!
This is how I've got my domain set-up. It's very simple to do - all you need is some PHP or Perl capabilities on your web-space. So far (six months on) my main email address still hasn't made it onto any spam lists, and I don't even have to filter it!
Hope this proves useful to someone
I've had a (personal) domain or two for 6 years or so, which just happens to have also had some domain contacts associated with it...and man oh man the spam. At one point there was a catch-all account, but now? HELL NO.
We accidently left it on for a month once and got 6,000+ in the catch-all account. No human being is going to sift through that many emails to see if ANOTHER stupid human being sent an email to the wrong address. If it's important, they'll make sure they sent it right.
Had catch-all's on both my personal domains and the domains owned by my employer. On two separate freeBSD/sendmail boxes I saw the same situation: horrible amounts of spam.
Turning off the catch-all's in my personal box was simple, after all, it is my own server and I can do whatever I want. Spam dropped like crazy.
Turning it off at the work server was different because the marketroids are paranoid about people not being able to reach them for sales issues. What I did was switch one domain per week and wait to see if anyone noticed a difference.
Nobody did.
Pedro
----
The Insomniac Coder
I use a catch-all address *against* spam; it's been proven to be quite useful. More details in this /. thread here.
No encryption can withstand the power of the Lucky Guess.
Just this week, I had to remove the catch-all on my two main domains. Something seemed to have happened to my Mail.app junk mail database after some work on my setup, and suddenly most of the spam was making it to my mailbox. A little investigation, and it became clear that it just isn't feasible to have catch-alls anymore. Most of the spam I was getting was sent to addresses that have never, ever been used before.
My Photography - http://ian-x.com
The Deathlings (comic) - http://thedeathlings.com
I used to find that I only got spam to postmaster, webmaster, admin etc...
Until one day some bastard decided to start selling an email list with every made up name he could think of @(mydomain).com.
At the time I had qgreylist running (It's a simplified version of grey listing which returns a temporary error unless it's had mail from that ip address before in the last coupld of months). This meant that I was getting a mere 300 spams per day, but without that I would have been getting considerably more.
Needless to say, I turned off the catchall, which was quite annoying, as it was useful to just enter (companyname)@(mydomain).com whenever a website asked for my address. Now If I want to do that I have to set up an alias, which is a pain.
AOL and Yahoo both recently seemed to start cracking down on the massive amounts of bounced messages they've been getting, because of forged return addresses pointing there from dictionary-attack spam. They've been (temporarily, but still) blackholing any mail servers that send them spam - even bounced spam from invalid addresses, bouncing to forged addresses within their domain.
A catch-all account (even if you don't read it) might stave the ire of the 'big boys'.
While all of that server stuff sounds interesting.... Set up the catch all email account.
Earthlink is my ISP and hosts my domain name. Thus, I have an earthlink email address. ALL email sent to my domain name goes to that Earthlink account. So, myname at mydomain, somebodyelsesname at mydomain... all go there.
1) Since I use the domain name as my email address, Outlook filters and saves myname at mydomain. However, ANY email to the Earthlink address is spam, since I have NEVER used that address, and so Outlook drops all of those in the delete bin. Any email to namemy at mydomain, yourname at mydomain.... are likewise spammers trying to figure out valid email addresses and are also spam. They go in the delete bin too. These two filter rules are the most effective spam rules I have in Outlook.
2) The exception to this is that Earthlink refuses to send me email at my domain, and so a third filter in Outlook saves emailed bills from Earthlink. Domain name renewal stuff, for example, I changed to reflect the myname at mydomain address.
3) When I go to a site that I don't want spam from, but I have to sign up for, I can enter the sitename at mydomain. Like gamerworld at mydomain. If I am expecting email from them (like a new password) I watch the delete bin for it. Otherwise, I don't worry about it. It's also a simple way to see if those promises of "we won't mail you anything, honest" are kept. Or to a tech forum. Sign up as techforum at mydomain, post your problem, watch the delete bin for a few days (or add the techforum at mydomain to your whitelist), post replies to your replies until you fix the problem, and then ignore that address (or remove techforum at mydomain from your whitelist).
I think everyone should get their own domain and filter email like this.... But it probably wouldn't work if EVERYONE did it....
Richard
When i set up my own domain, I did the same thing- it seemed like a good idea, not to mention the humor value of having my friends send emails to bizarre addresses. After one week of getting absurd amounts of spam to virtually every address under the sun @mydomain.com, I deleted the account.
Gentlemen, you can't fight in here! This is the War Room!
I have catch-all turned off on all my OLD domains. Over the years, they just ended up on too many spam lists. (Hey, back in the day, we didn't have to have "safe emailing". We used our email addresses all over the place.)
So I had to turn if off on old domains. On my newer domains I'm just very careful about where I post my email addresses. The server takes care of most general domain targetted spam.
It works for me, but maybe I'm a special case. I am able to give out special email addresses and then set up my local client to plop each into its own mailbox. That may not be something you do a lot, but it has sure worked for me. I just ignore the stuff that doesn't get filtered into a special location. Of course, you have to plan this from the very beginning and give out addresses that way. If one becomes a spam attracter, I just give out a new address for that slot and change the filter.
I will admit to getting lots of spam until my ISP recently implemented a wonderful spam filter.
A feature called greylisting will reject an e-mail for 45 minutes before accepting it. Most legitimate e-mail senders use RFC-standard SMTP servers which stick around and try to re-send the e-mail for the designated time period. This cuts down on SPAM quite a lot but will create a delay for suspicious messages and most first-time senders.
When I was an IT for a particular company the way it went was - if you did something well or did not appear busy, you were assigned more permanent responsibilities- or so it seemed. What I found was, if more spam went to the owners account (he was paronoid about missing a sales related mail so catch all was prescribed) then he was more likely distracted by either someones marketing, sifting through it all timewise, or the newest worm/trojan (I was not responsible for his personal system due to his remote location/paronoia/ego where he wouldn't take the time to update and anti-v setup (on XP LOL). His system constantly went down and he was aware of the fact that no other system went down as often (very often) so he would "diappear and try to get someone else to fix it cause of his ego". LOL LOL LOL LOL LOL less work for me!!!!!
I have a catchall at one of my domains and have spam assassin set to filter a high rate - then everything else is forwarded on to the account I use the most. I then have popfile filter it further, and finally thunderbird finalizes the spam filtering and I get all the imporant mail sent to the catchall but none of the spam. I could probably cut popfile out of the loop - except using its header modification it is much easier to filter all the email from all of my accounts into one set of folders in thunderbird - since thunderbird insists on using a different folder structure for each email account.
Just run some free filters, like spamassassin, it it with update of rulesets, bayesian filtering and vipul's razor and it kills almost 95% of spam messages.
I use to get about 120 or so messages a day, maybe 10 or 20 were real emails the rest was spam, now I get maybe 1 or 2 spam messages a day. Just be warned that you need to whitelist some addresses cause companies sending out 'product' updates look an aweful lot like spam to the filter system.
If you have spamassassin set up corretly it will kick ass!
-b
I've tried a lot of spam filtering methods to my domain and nothing has worked as well as training spamassassin. It's a bit of work at first, because you have to sort all your email in Spam and Ham (non-spam) but after a while it gets down to only a few spam emails a week which I also send through the trainer. Just checking my reject folder right now, I've got 612 spam emails in the last five days and only two got through. This is much easier and more effective than trying to write custom rules.
Far too many people at my work have unusual (and easy to misspell) names. I've seen three totally different spellings of my boss's name. But if it just bounces, the client won't bother to resend, and we need this information. So guess who now receives 20 e-mails a day, and thanks God for the blessing that is Thunderbird?
i have a catch all at earle at earlea dot com
spam ! you betcha,lol! i've rerouted all my domain e-mail through www.mailblocks.com now and THAT'S how i contain MY domains spam problems.
btw:
i tried a dozen different ways to creater an account to my liking. unable to do so.
so,i'll post as anonymous,lol.
earle at earlea dot com
As an e-mail administrator for a company who offers e-mail to the outside world, we had to deal with spam like everyone else running a mail server. Spam was the biggest complaint. We installed SpamAssissin, which helped, but it took up too much time to feed and maintain the filters. So, we bought our way out. We switched to modusMail by Vircom and haven't looked back. It catches close to 99% of our incoming spam, catch-all accounts and all. False positives are less than half a percent. Every morning each user gets a Quarantine Report showing all the spam and viruses for the previous day. From here they can whitelist or blacklist addresses of anything that was caught. Best of all, there is a dedicated team of spam-busters that does nothing but update the filters, which get pushed down to us every 6 hours. Spam doesn't make it to our desktop anymore, nor do viruses, and we spend less than 15 minutes a month managing the mail server. Yes, we paid quite a bit of money for it, and it's not open source (gasp!), but it WORKS, and the users are more than willing to pay extra for this level of service.
It's not possible, AFAIK, to give the sender an error message before the message is sent. All mail for a domain comes to the server, whether it's misaddressed or not. It's what is done with it that makes the difference. Blackholing misaddressed mail definitely saves bandwidth and server resources since there is no reply generated and nothing gets stored. Setting the server to generate a fail message is a courtesy and may be worth it for places where you might get messages that are important. As with blackholing, nothing is stored on the server and the failure message is quite small, AKA little in the way of bandwidth used.
.net TLD instead of our .com TLD. There was all sorts of misaddressed mail, incorrect only with respect to the TLD, so it was fairly easy, back in 1999 to manually reroute those to the .net address and send a note back to the sender explaining their mistake, but it eventually got out of hand since it was a manual process on my part and I finally had to quit doing it.
I have a domain where there is a local ISP in Iowa that has the same name, but with a
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
Recently, some virus infected computers, somewhere in the world, started sending out virus e-mail messages using [random-address]@mydomain.com, so I was receiving lots of bounces and virus notifications, so I disabled my catch-all.
- Eric, InvisibleRobot.com
The only problem with that analogy is that a computer is a multi functional tool.
Those functions can ( and often do ) vary widely.
If I use function A, and understand it 100%, that doesn't mean by default I understand function B.
It is ludicrous to base a persons intelligence on his ability to use function B, which to you and I seem rather 'self explanatory' in its usage.
Good example: Few would consider Einstein anything but insanely intelligent.. but he was incapable of picking out clothes for himself each morning.. something most of us take for granted...
---- Booth was a patriot ----
Just run your on email server dude!
(and catchalls in general)
Nowadays I'd really have to recommend against catch-all accounts.
We used to run a catch-all at a server I administer, it had been a thing of beauty for a number of years. Few spams to never-existant addresses (the occasional crap addressed to "info@" and "sales@" were about it), and the convenience of never having to keep track of the made-up-on-the-spot email addresses given out to shady people, registrations, etc. A few addresses got into the hands of hardcore spammers; these were replaced with an autoresponder politely directing live humans to another address.
Then, early this year, some Windows virus-or-other came out which sent mails to random and other novelly-generated addresses (joe@, bob@, username from another domain @yourdomain.com), and spread rapidly. Within a couple days, the catch-all account (read: my inbox) was receiving upward of 10,000 (yes, that's not a typo) copies of these huge Windows viruses per day.
Not only this, but those couple of autoresponders were also being hammered by mails from forged addresses, causing them to send a "this address is deprecated, please use..."-type mail (or lots of them) to people who never sent mail to that address in the first place. This included the administrator of one particular Debian-related mailing list, who I remember as being rather rude, threatening to get our domain UDPed, blacklisted, sent to Detroit or whatever is today's preferred form of vengeance from someone closer to the backbone than you are.
Needless to say, life with catch-alls ended for us in short order (with a couple months of occasional "what happened to your address, it's dead!" from people sending to addresses I didn't remember to create after removing the catch-all functionality), and life + my inbox returned to normal.
Caveat Emptor is not a business model.
The parent post is an example of one of those rare cases where slashdot needs the ability to give a +6.
Like many things in life the email system is poorly designed; however, that does not mean people should have to learn to cope with the deficiency. Doing so will only cause them to fear new technology.
By standing up and refusing to accept an inferior product, these users are actually challenging us [programmers] to come up with real a solution to the problem. If we cannot do that, then we're the idiots.
a lot to learn. I appreciate the input. While I've been running several websites for several years, my use of e-mail has not involved setting up mail servers, but rather using what the hosting services provided. What you say makes sense. One of the important things I come to /. for is to learn.
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
A catch-all address will indeed collect tons of spam and bounces from spoofed senders.
But sometimes there are some valid mails from people who mispelled your address.
RelayDB (http://www.benzedrine.cx) is a program you can run when receiving mail. "relaydb -b" means the mail is spam, "relaydb -w" means the mail is ham. Then, relaydb will maintain a database of "scores" of IP addresses.
If the "score" of an IP address is too high, it will be blacklisted. If some real mail comes later form that IP address, it will be whitelisted.
By feeding your catch-all address to "relaydb -b" you will filter 99.9% of the spam and Microsoft annoyances. By feeding your valid addresses to "relaydb -w", you prevent valid mail from being filtered, even when sent to your catch-all address.
{{.sig}}
No problem... I figured you were truly ignorant of SMTP operation and so provided a mini lesson.
SMTP is deceptively simply and immensely complex, at least "sendmail" is. You could implement the basics of an SMTP server with just a few dozen lines of perl code, but it takes tens of thousands of lines to completely do it "right".
Article X: The powers not delegated... by the Constitution...are reserved...to the people
It's definately worth it - telling my friend Rachel that my email address is rachel_is_my_sweetie@kezze.dk really flattered her - and by using a catchall-account, I can trick every girl that I meet, without having to get online and set up aliases.
They fall for it, that's for sure.
"Postmaster" is certainly a required mailbox for any SMTP server. That's an explicit requirement. However, "abuse" is not a required mailbox. RFC 2142 only requires that the "abuse" mailbox be recognized if the service exists. If you have an "abuse department" or someone designated to handle abuse complaints, that mailbox must reach them. RFC 2142 doesn't demand that any of the listed mailboxes be used -- it only exists to standardize the mailbox names so that you don't have "abuse" at one site, "tos" at another, and "complaints" at a third.
RFC-Ignorant.Org is promulgating an incorrect interpretation of RFC 2142, claiming that every domain must support an "abuse" mailbox, by interpreting even single-user domains as "organizations" and reading between the lines of multiple sections. If "abuse" truly were a required mailbox, it would be clearly spelled out in the RFCs as it it for the "postmaster" mailbox. No, it's not strictly required, especially in the case where the domain is run by a person on their own server, and no "organization" exists at all. It may be strongly recommended, but not required.
If "abuse" bounces, then the appropriate mailbox to use is "postmaster". What's the problem here?
Deven
"Simple things should be simple, and complex things should be possible." - Alan Kay
yeah, you're probably right.
Read my short stories - You won't regret it.