Slashdot Mirror
Spammers Exploiting Hotmail Vulnerability
chip rosenthal writes "Notice more Hotmail spam in your inbox recently? There is a good reason for that. In March, spammers discovered a new vulnerability in the Hotmail service that allows them to script their spam sending. So far I've seen a 2200% increase in Hotmail spam as a result. We're now at three months and counting, and the problem only seems to be getting worse."
Is it really possible to get even more spam using hotmail?
You expect Microsoft to be ahead of the spammers.
I had a hotmail account once, but the spam level got so high that I abandoned it. It was about 10 times heavier than say Yahoo mail. But now Yahoo is spamming up also, I cannot even imagine 10 times that amount. I think that harddrive makers are in kahootz with spammers.
Table-ized A.I.
If you check the box to list your new hotmail address on various partners' lists...ever wonder how that works?
InfoSpace was such a partner (maybe still is, but I don't work there anymore). Every so often Hotmail sends these partners a huge set of files. Basically, it's all the diffs, new users, etc.
All it takes is a few employees at a few such partners to copy the data and do whatever they want with it.
Of course, this is a very old problem...nothing unique to Hotmail...
[Set Cain on fire and steal his lute.]
I don't buy it. An hour with a Perl for dummies book and the LWP doc's and any spammer can automate thier submissions.
Does the author really believe that these spammers are copy and pasting thier spams? I sure as heck don't.
Karma: SELECT `karma` FROM `users` WHERE `userid`=138474;
Not to totally deride Hotmail, but after having used it for several years, I can honestly say that it's probably the worst out of all free e-mail providers in terms of controlling incoming spam. Yahoo Mail blocks out a good 80-90% of incoming unsolicited mail, and hushmail.com is even better at it - I haven't gotten a single spam during my 6 months with them (so far at least). Add to that the ease with which Hotmail passwords can be hacked (trivial even for script kiddies), and after some consideration you might want to look at another provider.
:)
And hey, it's owned by Microsoft! Grab your pitchforks!
"The power of accurate observation is frequently called cynicism by those who don't have it." - G.B. Shaw
The best use for hotmail always has been: Use the account only for entering onto forms that require a live email address that info will be sent to immediately in response to the form being filled out. Then beyond that, don't even bother checking, just periodically empty the inbox all at once.
You've been able to send email through OE and Outlook for years without utilizing the hotmail web interface. Outlook could easily be automated through COM to be a bulk mailer.
How is this any different than signing up for a standard throw away ISP account with imap or pop/smtp servers and using a bulk mailer in conjunction with it?
Another function added at the expense of security and usability.
...and a distinct lack of beer.
I get the distinct feeling that if Microsoft organised a piss up in a brewery there would be sausages, crisps, plenty of seating, a cool entertainment system, probably even a stripper...
Beep beep.
Hi. Welcome to Slashdot. You must be new here?
it isn't that Yahoo is "spamming up", it's that they've made "address blocking" as a part of their pay package. As a result you get more limited address-blocking capability with the free account, and it's easy to have them cycle through.
:-/
Also, I've noticed that some persistent spammers just get through, period, even with blocking [with no apprent change in the headers, at least none that are obvious].
go for the bonus round by getting a disposable email account (eg spamgourmet.com) to protect your new address.
who's moderating the meta-moderators?
Why would a nerd ever use hotmail? Don't they all have their own domains?
...and they shrugged it off, claiming it wasn't their problem. Hotmail actually pointed the finger at MSN, and MSN wasn't responsive when I included them in the loop.
.
Here's an example of the kind of brush-off I got when reporting this to Hotmail. Note that I've reported the issue several times, tried to have it escalated as I suspected it was a hole in their DAV implementation. Here's what I would get back from them:
Hello warthog,
Thank you for writing to MSN Hotmail.
This is Alvin and I'm writing in response to your complaint.
I have checked the mail including the headers and it appears that the
mail passed through a Hotmail server. However, kindly note that this
does not mean such e-mail originated from our domain.
Sometimes, e-mail delivery between different domains are relayed
through other servers. This is the reason why a Hotmail server appears
in the mail header. It is possible that your ISP or e-mail provider
employs such method.
I understand how it feels when an illegal activity has not been given
proper attention. However, we're only allowed to investigate Hotmail
members. In this case, I strongly suggest that you contact the Help
program or the Abuse section of the domain from which the unwanted
e-mail originated
Sincerely,
Alvin F.
MSN Hotmail Customer Support
Hotmail seems to receive more spam than other free email providers. I believe this may be due to how they handle recipient verification in SMTP. When a mail client attempts to send a message to an unknown username, the hotmail mail server will reply with an error message, indicating that the user doesn't exist. As a result, it is possible for a single spammer to spend some time just once to brute-force user names, and then distribute the list of known-good user names.
Yahoo generates the same reply regardless of whether the recipient exists or not. Thus, to guess user names, spammers would have to brute-force every mailing, as opposed to just the initial one like in the hotmail case.
Why hotmail would do something like this is completely beyond me.
Tsunami -- You can't bring a good wave down!
To plug bluebottle.com. Their 'smart' spam filtering system includes a challenge-response type system to verify the legitimacy of the account and an allowed list. I've been using it for about 2 weeks and like it so far (I get over a hundred pieces of crap a day at my old account).
Couple of nits are it is slow as hell to log into (they are in Australia and supposedly upgrading their system to fix this) and it uses Horde as the actual email interface (I'm a much bigger fan of SquirrelMail and always thought Horde needed a serious facelift).
Of course the upside is I haven't had a single piece of spam and I really like logging in and knowing that if I have new mail its from people I want to hear from.
Here's their marketing spiel:
Bluebottle stops spam.
Bluebottle's open-source technology is 100% effective in blocking unwanted email. It is the only system that can effectively protect a user from spam while ensuring all legitimate email is received.
Bluebottle is easy to use. When Bluebottle receives an email from an address or domain not on your âAllowed' list, a verification request is sent asking the sender to verify themselves in one of two ways. The required response to these verification requests automatically places the sender's address on your âAllowed' list, and the email is delivered to you without delay.
Once the sender's address is on this list, they can email you as they would normally. The advantage is that you ONLY receive email from allowed senders.
Effective.
To avoid identification, spammers commonly use forged or fake addresses. Consequently, the verification request is never seen or responded to, so spammers can't infiltrate your allowed list. That means you'll no longer receive annoying, unwanted email.
Manageable.
Bluebottle is easy to manage. Simply add your known contacts to your âAllowed' list so they can avoid verifying themselves. And even if legitimate senders do need to verify themselves, it's quick and easy to do so.
If you're sending an email, Bluebottle automatically adds the recipient's address to your allowed list to avoid a request being sent when they reply.
Protective.
Bluebottle applies the verification process to your existing email, including Hotmail, by checking your accounts through its servers. Email from known senders is delivered to your account without delay. Unknown email is placed in the pending queue to await verification. You can access your spam-free email through Bluebottle's webmail interface or via pop using any email client.
Quack, quack.
I always wondered how people get so many mail via hotmail while I do not
The only thing which I took care of, was to not click on "yes, send me spam from all advertisers", but that was a no-brainer. If you apply for spam, you will of course get it.
So far, I have my account for more than a year. I regularily send a mail once in 2 weeks to another account, with reply to keep it from expiring, but beside this I don't use nor advertise it at all. No spam. Zero. Nada.
It might be because I am non-american (so I am not a good target for american-only advertising).
Am I the only one with this "problem"?
Ugh...
Hotmail supplies me with the following things:
Slashdot Updates
Porn
Oh yeah, and I occasionally get asked if my privates are O.K.
Check.
------
The movie of the summer
***Insert Witty Phrase Here***
On March 6 I created a Hotmail account with a choice of name designed to be "really obscure". I have not had one single piece of spam arrive in that account. In 3 months, no spam. I've only used this account to test whether spammers use email addresses harvested from 551 User not local; please try really-obscure@hotmail.com SMTP responses (conclusion - no they don't)
Having see dictionary attacks on my own domain (and seen the bounces from dictionary attacks when spammers fake my source email address), I can conclude that geeks choice of obscure doesn't range far off science fiction character names.
As for this Hotmail exploit, I had been wondering why these spams were getting through my DNSBL lists - about the only spam that was.
Time to add hotmail.com to the baclklist until Microsoft fix this.
Recycle PCs and build a wireless community network www.hillsborough.org.nz
I've had my hotmail account for YEARS. I also have my regular DSL account, which NO ONE but those on my outlook adress book have. Why do I have hotmail? For online ordering, web site downloads etc. This way, ALL my junk mail goes into the hotmail account. I then use mail washer to filter out what hotmail can't (which is a bunch). I check it when I get home, dump the junk, then before I hit the sack. What a great service that Microsoft provides for us! Keeping the junk out of our "regular" inboxes, freeing up their servers, and clogging the MS ones ;)
THANKS MICROSOFT
I also get no spam in my main hotmail account other than the occasional (monthly?) message from the hotmail system itself.
I did once set up an account at sendmesomejunk@hotmail.com, and the box was filled in less than a week, mostly with stuff addressed to a single person, so I think it's possible that many people get spam because they picked an address that was already in use in the past, but abandoned.
On a mostly unrelated note, I once had an address that was me@myisp.net, and got tons of mail from people at my ISP that were trying to send stuff to themselves.
So please, I know slashdot will take any opportunity it can get to Microsoft-bash but in this case the blogger is pronouncing the sky to have fallen when it has not. The fact is that this service IS traceable and IS throttled, two aspects which make it relevent only to the newbie spammer that doesn't know what he's doing.
Since US butts are, on the whole, larger than in the rest of the world, I can guess that a metric buttload is larger than a US buttload.
Prime numbers are exactly what Alan Greenspan says they are -S. Minsky
0165 Jun xxxxxxx xxxxxxxxxxxxxx
1602 May xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
0734 Apr xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
0439 Mar xxxxxxxxxxxxxxxxx
0289 Feb xxxxxxxxxxx
0236 Jan xxxxxxxxx
0283 Dec xxxxxxxxxxx
0189 Nov xxxxxxx
0417 Oct xxxxxxxxxxxxxxxx
0349 Sep xxxxxxxxxxxxx
Clearly, I for one have been getting a surge in spam lately, which might possibly be sloping back down after last month's spike, but it's too early to tell yet.
In spite of that, of the nearly 3000 spams I have received since march, only seven match the pattern with DAV in the message headers. That bears repeating: I have received only seven instances of this exploit, vs. 2940 overall spams since March. Further, I only see 72 messages that have a hotmail.com server on their received headers at all -- most of the time I get "from Hotmail users" it's almost always forged.
Anyway, the first message to mention "with DAV" was sent March 25th, which fits the timeline this guy describes. On the other hand, the rest of my data massively disagrees with the 2200% spike that is suggested in the linked blog -- it seems to me that 0.238% of the spam I'm getting is due to this mis-feature, not 2200%.
Now granted, the two of us are the only two data points that I know of so far, but the results that we're seeing are so wildly out of step that I wouldn't think people should draw conclusions from this. Two completely conflicting measurements can't show us any kind of pattern.
The spam sky may be falling, but this isn't one of the falling pieces you need to keep an eye out for as near as I can tell.
DO NOT LEAVE IT IS NOT REAL
Honestly, though, blaming Hotmail for this is pretty counterproductive. 99% of the time, parsing the header and tracing the return path reveals that the the displayed information was munged and spoofed beyond any resemblence to reality. I have yet to have a spam bearing a Hotmail "from" address actually be sent from a Hotmail account.
Yes, Microsoft is (probably) guilty of a multitude of evils. This, however, doesn't seem to be one of them. Hotmail spam is increasing, just as is all other spam, because there are enough idiots out there who actually will click on links in unsolicited e-mail to make it profitable for the [expletive deleted] who send the shite out in the first place.
Doing my level best to piss off the religious right wing...
As much as I love to bash Microsoft, this isn't really a "vulnerability" in the normal sense. What they are saying is that when Microsoft lets you send mail through hotmail without a web browser, you can send mail through hotmail without a web browser. Duh. What's next, free POP/SMTP providers have a "vulnerability" that allows their users to send mail with their SMTP servers? And their claims of spammers otherwise being limitted to "copy and paste" is just ridiculous. Just because its a web interface doesn't mean it can't be scripted or can only be accessed by a normal web browser. Somehow I doubt that there are many spammers copy/pasting messages over and over into hotmail accounts.
----
All of whose base are belong to the what-now?
FWIW, Hotmail ran on BSD for a number of years, before Microsoft bought it out. They then sent a huge crack team of MCSEs (if such a thing exists :-) in to switch everything over to Windows, and they did everything apart from the advertising servers. It was run like this for a couple of years, then some Linux fanboi said "look! Microsoft use Unix!" and they changed the ad servers too. I've had my Hotmail account for around six years, and have been receiving stupid volumes of spam for about three years. Even when Microsoft took over, it was a useful service for a few years.
Of course, we all know Microsoft don't use UNIX at all, do they? In fact, they never did.
I created a hotmail account with an unusual name unlikely to be guessed by any kind of directory attack, and selected every privacy option I could find but within four hours I got spam.
How could that be without Hotmail leaking names?
About a month ago my mailserver started to receive a lot of hotmail connections from the range 65.54.*.*., guess what the bay range servers inside hotmail.com. I contacted abuse@hotmail.com, tried a few times to convince the drone at the other end that my mailserver was receiving a connection from a hotmail server every 20 seconds, but they didn't understand it. I mailed mailserver logs, explanations, links to threads about this on usenet, no clue. After a while I simply blocked all hotmail servers from my server. It's really weird that they have people on the abuse staff that do not understand what 'abuse' means or how to prevent it.
A week ago I removed the block to check if things had changed. To my suprise, no connection since. Apparantly MS has solved this problem finally (that is: installed the WebDAV patch that is what, 2 months old?).
Never underestimate the relief of true separation of Religion and State.
crack team of MCSEs (if such a thing exists :-)
Of course they exist!
MCSEs only use the finest crack.
Eve Fairbanks says I drive a hybrid!LOL