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Blocking faked HELO spam

J

jamesyeeoc

Guest
RH9/Plesk 7.5.x (need for 6.0.2 also)

I've managed to block over 95% of spam from coming into the server, but a lot which do come in are faking one of my valid IPs in their HELO reply, so even if I've firewall blocked their IP or put their @domain.tld into the blacklist, they are still able to dump their email into my user mailboxes.

I know there is a way to do it with Postfix, but Pf is not used on the Plesk box.

Is there any other way to do it ?

(not a newbie, am familiar with using CLI)

Thanks!
 
Well, if you have a PIX firewall, you can enable the smtp fixup protocol. I think that this checks the HELO to make sureit is not fake. Enabling this can cause other problems though.
 
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