Backscatter spam
Bounces to spam sent from forged addresses
Backscatter spam is a side effect of spam that has been sent with a forged 'From' address.
Automatically generated replies (such as failure notifications and out-of-office responses) are sent to
email addresses that did not send the original (spam) email, but whose address
had been used by the spammer.
Backscatter spam is hard to filter because of the many different ways mail servers send
delivery failures. However, by implementing techniques such as SPF and BATV,
backscatter spam can be greatly reduced.
