Re: [dmarc-ietf] Forensic report loops

Alessandro Vesely <> Thu, 14 January 2021 16:04 UTC

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Original-From: Alessandro Vesely <>
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To: "Murray S. Kucherawy" <>, Steven M Jones <>
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From: Alessandro Vesely <>
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Date: Thu, 14 Jan 2021 17:04:07 +0100
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Subject: Re: [dmarc-ietf] Forensic report loops
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On Thu 14/Jan/2021 16:24:33 +0100 Murray S. Kucherawy wrote:
> On Thu, Jan 14, 2021 at 1:22 AM Steven M Jones <> wrote:
>> On 1/13/21 20:29, Murray S. Kucherawy wrote:
>>> 3) always generate forensic reports as the null sender, and specify that
>>> forensic reports should never be generated in response to the null
>>> sender >>
>> I suppose that would meet the goal, but what would be lost along the way?
>> What keeps coming to mind is the advice I've seen to have your bounce
>> messages authenticate with DMARC - if a sender does that or is in the
>> process of implementing it, they might want whatever forensic reports they
>> could potentially get...

Another way is to set the From: domain to a subdomain having a DMARC record 
with neither rua= nor ruf=.  I use for aggregate reports.

> I'm also not a fan of the idea of treating different bounce messages in 
> different ways.  That seems like avoidable complexity.  Do we want to ever 
> send back a forensic report for something from the null sender, irrespective
> of what's in it?

It might be interesting to know if regular NDNs are authenticated all right. 
As they have the null sender, rule (3) prevents that feedback.