Re: [courier-users] Spam with Delivered-To header

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
> courier-users@lists.sourceforge.net
> Unsubscribe: https://lists.sourceforge.net/lists/.../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
courier-users@lists.sourceforge.net
Unsubscribe: https://lists.sourceforge.net/lists/.../courier-users