steve.freegard at fsl.com
Thu Aug 20 18:51:15 IST 2009
Kevin Miller wrote:
> I'm being bombarded with a ton of spam that claims to be from localhost (but the IP isn't in the 127. range). They are false NDRs, bouncing off of foreign servers. A large number of my users are being joe-jobbed, and the remote servers send the NDRs here. Here's a couple of examples from the the mail log:
> Aug 20 06:32:30 mx2 sendmail-in: n7KEVnN7025703: from=<qvmanifestation at grahamevinson.com>, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=localhost [220.127.116.11] (may be forged)
> Aug 20 07:34:33 mx2 sendmail-in: n7KFYJdI029611: from=<kzmatrimony at ivory.plala.or.jp>, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=localhost [18.104.22.168] (may be forged)
> I'd really like to be able to block them at the MTA level, but barring that, a spamassassin rule would do nicely. Anybody have a rule available that would fit the bill? There are too many sources to try to blacklist - I'd be playing whack-a-mole all day long.
> (I've been on vacation the past few weeks, so if this has been discussed please let me know the subject line.)
In the access-map as the connect tag inspects the IP address and the PTR
record which should work in this case provided Sendmail doesn't ignore
it due to the '(may be forged)'.
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