SPAM from own customers

Suresh Ramasubramanian suresh at
Tue Dec 2 19:23:40 UTC 2003

Michel Renfer  writes on 12/2/2003 12:50 PM:

> How will you deal with the problem, that one user can flood your
> SMTP Server with tousends of emails within 10-20 minutes?

Virus filtering

Rate limit (+ script to auto terminate user) and smtp auth on outbounds

Separate inbound and outbound smtp relay. Don't let your inbound MX 
relay for your dialup pool (some trojans take the rDNS name / hostname 
of the infected box and do nslookup -q=mx domainname)

Ask AOL for an scomp at feed - a lot of these trojan spams seem to 
target AOL users.


srs (postmaster|suresh) // gpg : EDEDEFB9
manager, security and antispam operations

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