Re: Swen Really Sucks

[Peter Busser <peter () trusteddebian org>]

Hi!

> Therefore, no IP, e-mail, or domain filter will solve the problem
> completely without filtering every single possible permutation of From:
> address that the virus spits out...

I use several procmail rules to filter out domains (microsoft.com, msdn.com,
etc.) in From: and From, To: (e.g. microsoft.com) and certain words in the
subject (e.g. Microsoft). Since the virus depends on looking like an authentic
message, it can't do too much randomisation of the domains and subject lines.
Of course the filtering is not perfect, but it still reduces the number of
virus messages hitting the inbox.

Removing messages with an executable attachment will also help of course.
Except with the messages sent to mailing lists that remove attachments
alltogether.

> and using the "From" address rather than
> the "From:" address for the filter doesn't work, either, because the "From"
> address appears to be a different non-randomized e-mail address, possibly the
> real e-mail address of the infected victim (? haven't read any forensic
> analysis on this point yet...)

Does this imply that your e-mail filter does not understand regular
expressions?

Groetjes,
Peter Busser
-- 
The Adamantix Project
Taking trustworthy software out of the labs, and into the real world
http://www.adamantix.org/

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