Re: [dmarc-ietf] Sender vs From Addresses

Dave Crocker <> Wed, 24 March 2021 13:55 UTC

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To: Ken O'Driscoll <>, Charles Gregory <>
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From: Dave Crocker <>
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Date: Wed, 24 Mar 2021 06:55:18 -0700
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Subject: Re: [dmarc-ietf] Sender vs From Addresses
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On 3/24/2021 4:54 AM, Ken O'Driscoll wrote:
> DMARC is intended to prevent unauthorised use a domain name in the 
> 5322.From header. This header was chosen because it is displayed in 
> MUAs and is the target of spoofing attempts in phishing campaigns.

It was also chosen because it is the only identification field that is 
always present.

As for display to user, there is no evidence that validating the field 
has any effect on end-user susceptibility to phishing.  It seems natural 
that it would; however in fact there is evidence that it doesn't.  
Still, the belief that it does persists.


Dave Crocker

Volunteer, Silicon Valley Chapter
Information & PLanning Coordinator
American Red Cross