Re: [dmarc-ietf] From: munging, was Ratchets - Disallow PCT 1-99

Alessandro Vesely <vesely@tana.it> Fri, 23 July 2021 10:08 UTC

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From: Alessandro Vesely <vesely@tana.it>
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Date: Fri, 23 Jul 2021 12:08:16 +0200
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Subject: Re: [dmarc-ietf] From: munging, was Ratchets - Disallow PCT 1-99
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On Thu 22/Jul/2021 21:51:25 +0200 John R Levine wrote:
> On Thu, 22 Jul 2021, Alessandro Vesely wrote:
>>>>  However, I'm not sure whether to actually RECOMMEND to do so.
>>> That's simple: no.
>> Yet, From: munging itself resulted from cooperation between dmarcers and MLM 
>> people, didn't it?
> 
> No, it came from AOL and Yahoo unilaterally using DMARC to outsource the cost of 
> their security breaches, with the entirely predictable (and predicted) effect 
> of breaking every mailing list in the world.  List operators had to scramble 
> and come up with some hack to mitigate the damage when I became clear that AOL 
> and Yahoo did not care.


That certainly was the efficient cause of the trouble.  But you must remember 
that the possible solutions were discussed on this list with MLM participants a 
few years ago.  For example:

https://mailarchive.ietf.org/arch/msg/dmarc/KvSFv66Mz8UipXQ0477UgO5WKio/


Best
Ale
--