We started seeing these kinds of spam some time ago and in response wrote a custom perlfilter that rejects messages with a Delivered-To containing one of our hosted domains. So far it has not blocked anything it wasn't supposed to and we no longer see the bounces.
-Bob Bill Merriam wrote: > I have started to receive spam with a valid recipient address in my > domain, an envelop sender which is an invalid address in my domain and a > Delivered-To header already present showing it was delivered to the > addressed recipient. > > Without the Delivered-To header the normal thing would happen, it would > be quarantined by my spam filters. Because the header is already there, > Courier says "Mail loop", and tries to send a DSN to the invalid > address. That fails, so it goes to Postmaster. That forwards to me and > the spam filters quarantine the mail. The end result is still the same, > sort of. > > I don't know if including the Delivered-To header is an effort to get > around spam filters or just an incompetent spammer. I could stop this > by rejecting mail that fails SPF but then I have the classic problem of > rejecting all the mailing list mail I receive. > > It seems like everything is happening just the way it is supposed to and > anything I might do to respond to this will just break something. Is > anybody else getting these kinds of spams? Should I do anything about it? > > Bill > > ------------------------------------------------------------------------- > This SF.net email is sponsored by DB2 Express > Download DB2 Express C - the FREE version of DB2 express and take > control of your XML. No limits. Just data. Click to get it now. > http://sourceforge.net/powerbar/db2/ > _______________________________________________ > courier-users mailing list > [email protected] > Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users -- Earl (Bob) Kinney Unix Systems Administrator Harvard-MIT Data Center ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ courier-users mailing list [email protected] Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
