Good afternoon list.
We have a problem of a number of our clients which appear to have been
affected by malware/bots.
these clients use our servers as a smarthost.
The messages are similar, so creating a spam filter for spamassassin has
been done.
I have noticed that the sender is either a gmail, yahoo or att.net address.
Sender verification checks are passing as these providers appear to have
accounts setup for the random senders and are accepting mail.
Is there a way to discard the bounce backs for these forged senders?
Yahoo has blocked us due to the large number of mails sent, which i am
assuning is the bounce backs.
your help is appreciated.
many thanks
Tom
