Re: [Shutup] [ietf-smtp] Proposed Charter for something

"Christian Huitema" <> Thu, 10 December 2015 18:48 UTC

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From: "Christian Huitema" <>
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Date: Thu, 10 Dec 2015 10:48:41 -0800
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Subject: Re: [Shutup] [ietf-smtp] Proposed Charter for something
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On Thursday, December 10, 2015 7:16 AM, John Levine wrote:
> ... 
> >The real question is: would spam filters still be able to do a good
> >enough job if we removed these things?
> No, it's not.  The question is whether there would be an overall gain in
> privacy since providers would likely be less able to combat phishing and
> other privacy attacks.
> Spam filtering is just part of it, and in this case not where the most
> effects would be.

I am not sure I understand correctly, but it seems the reference to phishing
is in the context of "impersonated users." Bob receives a mail that appears
to come from "" Everything matches, SPF, DKIM, DMARC. So
Bob actually believes the mail comes from Alice, and opens the attachment.
But the mail actually comes from the evil Eve, who somehow managed to
acquire Alice's password, and submitted the phishing message by
authenticating as Alice to Alice's MSA. In that context, if Bob's UA notices
that the submission IP comes from Upper Nowheristan instead of the usual
Mirrorland, Bob's UA could pop up a warning, or block the message. Is that a
correct summary of the concern?

-- Christian Huitema