As others will no doubt point out, SpamAssassin is not a virus scanner, and if 
you getting viruses through your gateway you should be looking for a better 
virus scanner...

That said, I would use "body" tests rather than "full".  Body tests will strip 
out invisible HTML codes from the mail, so you can match text as your mail 
reader displays it.

Also, I would avoid trying to match a very long text string.  Rather, look for 
unique keywords or phrases, like:

body     VTEST1   /to send a huge amount of junk email/
describe VTEST1   phrase found in virus mails
score    VTEST1   2.0

body     VTEST2   /compromised and now runs a hidden proxy/
describe VTEST2   phrase found in virus mails
score    VTEST2   2.0

body     VTEST3   /instructions in order to keep your computer/
describe VTEST3   phrase found in virus mails
score    VTEST3   2.0


It's best to make a set of rules and eith use additive scoring or a META rule 
to combine them.  That way, the occasional mail that may match one test will 
not be killed.

Pierre Thomson
BIC


-----Original Message-----
From: Matthias Keller [mailto:[EMAIL PROTECTED]
Sent: Tuesday, July 27, 2004 8:46 AM
To: [EMAIL PROTECTED]
Subject: Trying to catch those latest virii....


Hi

There seems to be a virus spreading, I've received it several times, it 
goes like this:
Subject: Returned mail: see transcript for details
Body:

Dear user of <maildomain>,

We have received reports that your email account has been used to send a huge 
amount of junk email during this week.
Obviously, your computer was compromised and now runs a hidden proxy server.

Please follow our instructions in order to keep your computer safe.

Best regards,
<maildomain> user support team.

attached is a .pif file no virusscanner (yet?) detects as spam.

So I wanted to write a rule against those sentences, but whatever I try, 
no rule will match....

I tried:
full    _MKE_xVIRUS1    /We have received reports that your email 
account has been used to send a huge amount of junk email/i
full    _MKE_xVIRUS2    /Obviously, your computer was compromised and 
now runs a hidden proxy server/i
and added for each one a score and a description
I also tried body, rawbody but still NO match at all!
The Mail has a MIME Type of  multipart/mixed
and the first part is:

------=_NextPart_000_0001_F824EC38.FBF36544
Content-Type: text/plain;
        charset=us-ascii
Content-Transfer-Encoding: 7bit

<here comes the mail body...>

Am I doing something wrong that my rules wont trigger? The file should 
be read as other rules out of the same file matched regularly over the 
last few days...

Thanx

Matt

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