Messaging Gateway

We are being hit hard with backscatter spam and brightmail does not seem to be blocking any of it.  Any ideas what changes I can make to the filters to stop this spam?  We have users randomly get 2000-3000 messages at a time before it stops.  Thanks.

We are running Symantec Brightmail AntiSpam and AntiVirus Version 6.0.5.24.

Thanks very much for any replies!

Hi Kim,

Whilst this is a fairly easy problem to address with  Brightmail Gateway, it's a little different with Brightmail Message Filter (formerly SBAS) because we aren't controling or modifying the outbound mail (except in the case of outbound AS/AV).  In order to confidently protect against FPs whilst blocking backscatter, your MTA infrastructure needs to provide verification that it the undeliverable message came from your environment in the first place.  The way that is generally done is to add a header to each outbound message with an encrypted hash value that is tied to a private key only your MTA knows.

So, which MTA do you use with your deployment of Brightmail Message Filter?

I ask because MTAs such as postfix and, i think sendmail, have plugins for things like BATV already.

HTH

--ian

I'm using Microsoft Exchange 2003 on a Microsoft Server 2003. Do you know how I would set those up to include the encrypted hash value in the header? Thanks!