Re: DMARC methods in mailman

Philip Homburg <> Tue, 20 December 2016 11:06 UTC

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Subject: Re: DMARC methods in mailman
From: Philip Homburg <>
Date: Tue, 20 Dec 2016 12:06:01 +0100
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Just a random idea, I don't think I have seen it before, but I may have missed

What about adding a checkbox in the mailman profile for subscribers of the
lists that basically says: if you detect that the sender is using DMARC then
please rewrite the From header.

This way everbody who is completely ignoring the silly DMARC stuff sees no
difference. And everybody who uses DMARC for scoring can still see the original

People who receive the list on a yahoo account would have to mark the checkbox
(though maybe a list of default domains can be hacked in such that new
subscribers for those domain would get it set automatically)

It's a bit of coding, but it should result in almost no damage except in the
specific case of somebody on yahoo (or similar) receiving a post from somebody
from a DMARC protected domain.