Dnia 12.07.2021 o godz. 10:46:26 Ken O'Driscoll via mailop pisze: > > My understanding is that they don't accept unauthenticated messages, not > just limited to a DMARC policy. > > So, if your mailing list is sending messages with yandex.ru in the > 5322.From (visible From) address but the messages are not DKIM signed > using yandex.ru as the signing domain and the 5321.From (return-path / > envelope) address is different, then they look like spoofing and will be > rejected.
It may be even possible, that by "authenticated" they don't mean DKIM signed, but they mean SMTP AUTH (yes, on port 25!). I encountered this once with one Polish email provider. They required SMTP AUTH for all messages received on port 25 with the sender from their domain and rejected the messages if the session was not authenticated. A crazy idea, but they did exactly this. -- Regards, Jaroslaw Rafa [email protected] -- "In a million years, when kids go to school, they're gonna know: once there was a Hushpuppy, and she lived with her daddy in the Bathtub." _______________________________________________ mailop mailing list [email protected] https://list.mailop.org/listinfo/mailop
