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[dmarc-ietf] Re: Assessing the connection between ARC and the malicious impersonation problem

John Levine <johnl@ietf.email> Sun, 26 July 2026 21:42 UTC

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Date: Sun, 26 Jul 2026 17:42:45 -0400
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From: John Levine <johnl@ietf.email>
To: dmarc@ietf.org
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CC: brong@fastmailteam.com
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Subject: [dmarc-ietf] Re: Assessing the connection between ARC and the malicious impersonation problem
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It appears that Bron Gondwana  <brong@fastmailteam.com> said:
>-=-=-=-=-=-
>
>On Sat, Jul 25, 2026, at 13:07, Douglas Foster wrote:
>> Essentially all malicious impersonation come from clients of bare-metal hosting services, when those hosting
>services do not restrict outbound SMTP. 
>
>I'd be interested to know if other receivers agree that this is their main source of impersonated email in 2026.

These days I get as much from Sendgrid* as from anywhere.  It's not
subtle, obviously fake unsub links and the like.

R's,
John

* - we don't care, we wouldn't even know how

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