Jeff Abrahamson skrev den 2020-12-15 12:17:
I received an obvious fishing mail today from ad...@p27.eu (my own domain). I appear not to be running an open relay (say the sorts of websites that offer to check these things), and yet this happened:
why do you accept your own domain in port 25 as envelope sender ?, you should reject this
Am I reading this wrong? Why was that able to happen? I would have expected a reject because something that is not my domain claimed to be sending mail from my domain without authentication.
its not openrelay, but 100% forged sender domain, there is no dkim problem, aslong as opendkim does not see client ip as internal network, then it would be dkim sign of forged sender :/
why spammers try it is that spamassassin naively have whitelist_from, you should not use this, but only test on whitelist_auth