AOL Bans Mail From DSL-Hosted Servers

kmself writes "As first reported at linux-elitists by Aaron Sherman, and with a demonstration of the denial at zIWETHEY, AOL has begun blocking mailservers identified with residential DSL lines as an anti-spam measure, apparently heedless of the huge collateral damage this move imposes (and guess who can't send mail to Mom...). This action was unannounced, and has received virtually no coverage, spare an oblique mention at News.com. It also violates SMTP RFCs, as Aaron points out, not to mention the 'good neighbor' conventions of Internet communications. Mail to AOL's postmaster is also bounced -- this is RFC-ignorant. I strongly recommend that as a compensatory measure, non-AOL MTAs be configured to deny all incoming mail from AOL's domain."

Comments

bouncing mail to postmaster?

[fyonn]

I thought that was a requirement of having a domain and you can lose the domain if mail is not accepted or read there? I'd have to check the rfc's but wouldn;t that be a thing, someone taking aol's domain from them because they don;t accept mail for postmaster?

dave

Re:bouncing mail to postmaster?

[Anonymous Coward]

It would never happen. That would be like a multi-billion dollar technology company like, oh, say Microsoft, forgetting to renew their domain registration.

Not in our lifetimes :)

Re:bouncing mail to postmaster?

[Zocalo]

Nope. It's actually in RFC2821 section 4.5.1 - Minimum Implementation:

Any system that includes an SMTP server supporting mail relaying or delivery MUST support the reserved mailbox "postmaster" as a case-insensitive local name. This postmaster address is not strictly necessary if the server always returns 554 on connection opening (as described in section 3.1). The requirement to accept mail for postmaster implies that RCPT commands which specify a mailbox for postmaster at any of the domains for which the SMTP server provides mail service, as well as the special case of "RCPT TO:" (with no domain specification), MUST be supported.

SMTP systems are expected to make every reasonable effort to accept mail directed to Postmaster from any other system on the Internet. In extreme cases --such as to contain a denial of service attack or other breach of security-- an SMTP server may block mail directed to Postmaster. However, such arrangements SHOULD be narrowly tailored so as to avoid blocking messages which are not part of such attacks.

Note that there are no punitive measures are listed at all, in fact the worst that can happen for bending an RFC is that you will be named and shamed on a site like www.rfc-ignorant.org and maybe be blocked by some system admins. If you actually *break* the protocol on the otherhand, then things will probably get a little more ugly... ;)

Re:bouncing mail to postmaster?

[ajs]

It's worse. Here are the ways that I know AOL is violating RFCs for valid mail traffic:

1. Mail bound for postmaster@aol.com is not accepted.

2. They issue a 550 response before the client has a chance to issue a greeting. There are two allowed responses at that point: 554 and 220. 550 is right out.

3. They disconnect before the client issues a "QUIT" command or times out. Also bogus.

AOL is playing a game of chicken here to see how much of the net will blacklist them for breaking the RFCs. Once they smell blood in the water because not enough sites care, they can pretty much start writing their own book....

No problem

[JanneM]

I long ago includedevery mail from aol.com, yahoo.com and hotmail.com in my static spam filters. If anybody with such an account wants to mail me, they need to get in touch with some other account (or other means) first so I can add an excemption to them. To date I have three such excemptions total, all on yahoo.com.

I can't very well block them further than I already do, in other words.

Your Mom

[Anonymous Coward]

Don't worry, I am on AOL. I will send your mom a note.

In other news

[Anonymous Coward]

The United States Postal Service has announced it will stop delivering
any mail from Florida, due to the large number of mail-order scams
originating from that state.

Eathlink does this too.

[statusbar]

My friend pays for a "static" Ip address on his cable modem to run some private corporate web forums. A few weeks ago, all email notifications from the forums going to anyone hosted at earthlink.net were bouncing - The message is "No email accepted from dynamic IP addresses".
Both AOL and Earthlink have TONS of subscribers.

If they both decide to carry on doing this, there is nothing you can do about it.

Truth is, SMTP sucks. They are only doing this because of all the spam. Yes they are violating RFC's. Too bad...

--jeff++

It's their network.

[cperciva]

If AOL doesn't want to accept your mail, that's their choice. It's their network, and their mail servers. Of course, when AOL customers find that they can't receive any email, AOL might lose business.

Like all other spam blocking attempts, there will be collateral damage. They try to keep their customers happy, and the market decides if they succeeded.

Re:It's their network.

[Boss, Pointy Haired]

Yes, but have they told their subscribers?

You don't know you haven't got what you didn't get.

Good move

[Adnans]

If you have DSL you should still use your upstream SMTP server for outgoing mail. About 90% of incoming SPAM on my box originates from Windows boxes on DSL lines with open relays. I've set up exim to ignore all incoming SMTP calls from dsl hosts (*.dsl.*) and also to block hosts without proper reverse-DNS. These 2 simple steps take care in blocking a huuuge quantity of incoming SPAM at the doorstep...It's not fullproof, but it helps a great deal.

-adnans

Re:Good move

[SWroclawski]

I currently don't have mod points or you and others who have said the same thing would be modded up.

There's no RFC that says you have to accept mail from *everyone*. You're free to bounce mail to whomever you like.

As to why this is an effective technique:

1) Most of these "home servers" don't have a PTR record at all.

2) Those that do, almost NEVER have one pointing to the domain they claim to be recieving for.

3) All these residential users should be using their ISP as a relay. That's what the ISP is there for.

4) Since there's no reason for them to need to send it out *not* through the ISP as a relay host, the majority of these users are spammers or just ignorant. In the first case, it's good to block them. In the second, maybe they will get a clue.

I'm generally against crippling services on the ISP end, but I've even thought that maybe it's high time that ISPs do what AOL does, and block outbound port 25. Incomming is another story, but as the parent and I have pointed out- the residential users should be using their ISP's mail servers as relay hosts.

- Serge Wroclawski

You want these rights for *YOUR* MTA, right?

[Cirkit]

I'd expect users of RBLs (see http://www.spews.org) and certainly the denizens of NANAE to argue that they have the right to refuse to receive email from anyone, for any reason, since that mailserver is private property.

It can be used in ways you like (refusing emails from Verizon's corporate HQ because they refuse to kick their spammers) or in ways you don't like (making it more difficult to send outgoing mail), but I don't see how you can reasonably kick and scream against one and not the other.

Actually, several providers have been refusing email from dial-up pools for a year or more, which is what caused me to decide that I would need to send outbound email through my ISP. IIRC, attbi refused email from my server on my ISDN line over a year ago.

The solution isn't difficult - go dig around on your ISP's website (or call them) and figure out the mailserver that you'd be using if you WEREN'T running your own MTA. Set your mail server to relay outbound emails through them. (See your man pages - it isn't difficult.) There's NO way your ISP's mailserver is going to refuse to accept your email, since if they did, no one not running an MTA could get email out. Sure, you'll have an extra line of headers in your outbound email, but it doesn't seem like such a big deal. Was the location of your mail server a secret anyway?

Of course, if your ISP is a notorious hoster of spammers, you're going to need to find a new ISP. You didn't really want to support those spammers anyway, did you?

Re:Privatized mail

[LamerX]

I dont' understand why everyone is so down on the USPS. I've never seen packages arrive late. My mail, which sits out in an unlocked box on the street, never gets messed with, it always arrives at its destination, and it seems to get there pretty quick. I mean, which method do you notice EVERY company sends out bills? I've never seen anyone send bills via UPS or FedEx, even though according to many people the USPS sucks....

Re:Privatized mail

[EvilTwinSkippy]

The can't tweak it too hard.

According to the constitution, by law Congress must provide a postal system. Short of a constitutional ademendment, they are just a lawsuit away from any "reform" ideas being thrown out.

And frankly our postal system is a bargain. Try sending 2 oz letter 3500 miles for $0.36 in any other country in the world.

Now if you only had a telephone and a broadband service like that...

Re:ummmm...

[darkonc]

One thing that you can do is foreward your email through your ISP. If you're using Sendmail this is done with the smarthost entry:

# "Smart" relay host (may be null)
DSmail.MyISP.net

would forward youre spam (er, email) through the box mail.myISP.net . Most ISPs have a designated server that will allow email forewarding from anybody in their network space.