[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <200403060433.i264XFP308350@milan.maths.usyd.edu.au>
From: psz at maths.usyd.edu.au (Paul Szabo)
Subject: Re: E-Mail viruses
Curt Purdy <purdy@...man.com> wrote:
> ... dropping all non-priority [not named .dps] attachments ...
> If anyone gets ugly who happens to know the priority extension,
> the AV gateway will get it anyway.
Will get it, maybe, as well as until now. Maybe, because some (broken) AV
refuse to look at "randomly named" (e.g. non-EXE) attachments. As well, or
as badly, as until now, because AV does not "get" malware not yet in its
database; it never gets the new viruses, only the "boring old" ones.
Your arrangement may offer some protection from the deluge of common
viruses (allowing bits of each message through, instead of dropping them
altogether: still annoying to your users). However, it does not increase
your security (in the sense that you are still vulnerable to directed
attacks). Since your arrangement protects against some attacks, and does
not decrease security, it may be useful in some environments.
Cheers,
Paul Szabo - psz@...hs.usyd.edu.au http://www.maths.usyd.edu.au:8000/u/psz/
School of Mathematics and Statistics University of Sydney 2006 Australia
Powered by blists - more mailing lists