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Re: [dmarc-ietf] ARC vs reject

Alessandro Vesely <vesely@tana.it> Sun, 06 December 2020 13:40 UTC

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From: Alessandro Vesely <vesely@tana.it>
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Date: Sun, 06 Dec 2020 14:40:46 +0100
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Subject: Re: [dmarc-ietf] ARC vs reject
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On Sun 06/Dec/2020 02:34:45 +0100 Michael Thomas wrote:
>>
>> 5) The work you and Alessandro have done with reverse transformation is more 
>> likely to produce a solution for the mailing lists.   The lists will continue 
>> to do From rewrite, but reverse-transform recipients can validate the true 
>> source of the message and restore the From if desired.
> 
> I'm starting to get a little more serious about my quip that the MLM can insert 
> a sed script in a header to unmangle the message since it knows what transforms 
> it has done, unlike the receiving MTA trying to guess the common transformations.


But then the receiving MTA will have to guess whether the sed script 
considerably alters the intended meaning of the message.  For example, does it 
change a bank account number?


Best
Ale
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