On (2002/09/23 14:39), Mike Meredith wrote:
> I'm thinking of enabling :-
>
> deny senders = :
> condition = ${if ! eq {$recipients_count} {1} {yes}{no}}
> message = Invalid use of null sender
>
> to block mails with "<>" as the sender address *and* multiple
> recipients. The reason for this being the occasional mail virus/worm
> that uses this sender address.
This rocks. :-)
However, note that there are broken MTAs out there that bounce messages
to the address(es) in the From header. I've never bothered to find out
what they are; for my application, it's sufficient to know that they
exist.
This may affect your decision to enable your check, which I've enabled
as:
deny senders = :
condition = ${if >{$rcpt_count}{1} {1}}
message = invalid use of null sender
In my environment, losing bounces from said broken MTAs is an
acceptable price to pay.
Ciao,
Sheldon.
PS: Man, did the spammers go off this week-end or what!?