Re: DMARC and yahoo

Hector Santos <> Sun, 20 April 2014 17:23 UTC

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Date: Sun, 20 Apr 2014 13:23:10 -0400
From: Hector Santos <>
Organization: Santronics Software, Inc.
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To: Jeffrey Altman <>, Theodore Ts'o <>
Subject: Re: DMARC and yahoo
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On 4/20/2014 12:52 PM, Jeffrey Altman wrote:

> I took a different approach.  I left the bounce detection on but switched all accounts to digest mode.  Since the mail now comes from the list instead of the sender there are no rejections.   Not a perfect solution but it prevents harm to list participants.

Thats a good tip (Digest Mode) to pass on to our list operators.  Thanks.

However, what you going to do with when other domains begin to flip on 
the strict DMARC policy switch.  There will be more domains doing this 
now that Yahoo is showing the payoff is high in increasing the 
security quality of their domain.

Keep in mind that this is just about dealing with the legacy existing 
user accounts. You SHOULD still honor the policy for at least new 
subscribers from accounts.  You SHOULD also honor the policy 
for new submissions. But you believe you MAY ignore it and do some 
things to get around the domain's security policy.

The key is how to do all this in an automated protocol fashion, and it 
should begin with first honoring and correcting the DMARC draft 
specification for 3rd party resigner operations which it lacks.