Re: [dmarc-ietf] Tickets 98 and 99 -- fake reports are not a problem and if they were authentication would not help

Michael Thomas <> Mon, 25 January 2021 18:28 UTC

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From: Michael Thomas <>
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Date: Mon, 25 Jan 2021 10:28:55 -0800
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Subject: Re: [dmarc-ietf] Tickets 98 and 99 -- fake reports are not a problem and if they were authentication would not help
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On 1/25/21 10:23 AM, John Levine wrote:
>> The list seems to be digging in because no one has raised a use case that
>> shows a need to revisit the text. This was made worse by asserting that
>> reports must be authenticated, when the text already makes that clear.
> I think the use case is my proposed https reporting. If you think it
> would be useful to allow domain authentication, it's easy enough to
> say that the client SHOULD send a client certificate. Nobody will, but
> every https server and client library I know supports client certs so
> it's not hard to implement.

Which means that is done completely in bad faith. No thanks.

> I continue to believe that authenticating the domain sending reports
> is of no value, since there is no way to tell what if any connection
> that domain has to the IPs in an aggregate report or the IPs or
> domains in a failure report. If I wanted to send fake gmail failure
> reports, I would register and send 100% perfectly
> aligned fake reports from that domain.
I send mail to gmail. I send no mail to gmail-reports. If anything you 
are demonstrating even further that this is at best underspecified.