On 10/31/2016 03:08 PM, Eric Searcy wrote: > > That reminds me. I have a proposed idea for another nice-to-have, that > I'm mentioning now in case it has any impact on the architecture you are > describing. Some email systems (e.g. Exchange) do not accept any > inbound email crossing their edge that uses their own From domain. It's > like a tiny microcosm of DMARC but only for their domain, and there is > no way for the outside world to know about their policy. However, when > a member of the community says they get all list messages *except those > from their colleagues*, it's clear they have this kind of setup. It > would be great to have a customizable-by-sender-domain munge-or-wrap > filter that let me add other domains to get the same treatment as > domains that don't publish DMARC -- even if not needed for general > receipt of their messages, so that emails to others at the same domain > on the list can be received. (This functionality doesn't exist in mm2 > either.)
Adding Mailman-Developers to the recipients. As I noted in the original thread, this would not be difficult to add, but it won't be in the initial implementation of DMARC mitigations for MM 3 (see <https://gitlab.com/mailman/mailman/merge_requests/215> for more on that). However, I've just become aware that Microsoft has implemented another "feature". So far, the info I have is this is limited to their "hosted mail services", but it may well spread. What they are doing is looking at incoming mail for signs of spoofing/phishing and if found, they place a prominent notice This sender failed our fraud detection checks and may not be who they appear to be. Learn about spoofing<http://aka.ms/LearnAboutSpoofing> in the message. The issue for us is that one of the tests is the To: and From: addresses are the same. That means that any message To: a list with DMARC mitigations applied will be sent From: the list and any recipients using these Microsoft services will see that warning in the list message[1]. How long will it be before this spreads to all Microsoft email services <sigh>? [1] I first became aware of this via the thread at <http://lists.mailscanner.info/pipermail/mailscanner/2016-November/104001.html>. There it was the poster who saw the warning in his copy of the list message and mistakenly thought it was a rejection of his post to the list. The reply at <http://lists.mailscanner.info/pipermail/mailscanner/2016-November/104017.html> has interesting info. -- Mark Sapiro <m...@msapiro.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan
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