[Mimedefang] Re: New X-AntiAbuse way for spammer (Pierre Forget)

Dirk the Daring dirk at psicorps.org
Sun May 18 15:09:50 EDT 2008

On Sat, 17 May 2008, Pierre Forget <pierre at pierreforget.com> wrote:

> got them. But they still go through. Any idea how to get rid of this?
> Here is an example header:
> Return-Path: <rmaryland at newadvent.org>
> Received: from oemc8b286a37b8 ([])
>         by mail.hebergement-quebec.net (8.13.7/8.12.11) with SMTP id

     You should have dropped this moron at HELO. Waste of good bandwidth, 
disk, CPU and RAM to actually queue that garbage and run it thru SA.

     What tipped this idiot's hand? The HELO isn't an even vaguely an FQDN, 
so there was never any reason to let the retard get to MAIL FROM:, let 
alone send RCPT TO: or even issue DATA.

     Invoke MIMEdefang with -H for HELO filtering and include a filter_helo 
function. Reject (as in "terminate with prejudice") any connection that 
gives a HELO that isn't an FQDN, or is an FQDN from a foreign host that 
claims to be in your Domain(s), or is an IP literal not enclosed in square 
brackets, or is an IP literal that doesn't match the actual IP of the 
sending host (which will also catch foreign hosts sending an IP literal of 
one of your hosts, as well as IP literals like loopback and 
private/non-routable addresses). Hopefully you have split your border MTAs 
from your MSAs for legitimate users and you can also reject M$ 
LookOut!-esque garbage like "localhost.localdomain".

     The MD Wiki has some example code for such filtering.

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