mailing list archives
Re: Mail Servers blocking BAD Helo
From: Fernando Amatte <famatte () gmail com>
Date: Thu, 30 Dec 2004 18:20:42 -0200
I faced a similar problem, for a long time I managed ISPs and we
decided to use Qmail ( www.qmail.org ) with SPAMCONTROL (
http://www.fehcom.de/qmail/qmail.html ) as our SMTP server.
SMPT RFC says that HELO field must be the FQHN, but when you are
working with "windows" customers you have a problem ( another one ) .
Outlook Express send HELO as the "Machine's name". So we decided do
not DNS Lookup for the HELO/EHLO greeting, but use a good and well
done blocklist ( badhelo ) with regex.
This way we can block some kind of virus, automated Spam programs and
thinks like you tell, just including another line on badhelo file.