> From: Michael Deutschmann > > Some honest users need to send mail with "From:" and envelope-from > > different from $authenticated_id . For example, *-owner @ yahoogroups.com, > > @ ieee.org - they don't offer outgoing relay, only incoming forwarder. > > Supporting that is problematic. If the user specifies a forged envelope > sender and the recipient refuses it in-transaction, you will backscatter > at that envelope domain.
The combination of forged+refuses+backscatter is caused by spamming. The refusals are usually because spammers' email address lists are very dirty (lots of nonexistent addresses). Earlier in this thread I gave the link https://github.com/Exim/exim/wiki/BlockCracking That code checks rate of the refusals and will catch and block the spammer or the password he stole and abused. -- ## List details at https://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
