[ILUG] [OT] FYI: Don't trust MIMEsweeper

[Lars Hecking]

Justin Mason writes:
> > Previous messages to this list indicate that some sites are using
> > MIMEsweeper to scan outgoing messages for viruses. I just wanted
> > to let everyone know that my hacked-up postfix/amavis-perl/sophos
> > config caught a copy of the 'Troj/Knijpme' trojan in a mail message
> > signed by MIMEsweeper.
> 
> And the amavis stuff doesn't append obnoxious 10-line sigs while it's at
> it!
 
 amavis appends an X-AntiVirus: header if configured so.

 Attaching a 10-line sig is technically possible, but not recommended,
 as it would break MIME and digital signatures. The mail system must
 not modify mail messages (ugly hacks like stuffing the old message
 into message/rfc822 and wrap a multipart/mixed layer around it don't
 count :)