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Re: [ietf-dkim] Mailsploit

Grant Taylor <gtaylor@tnetconsulting.net> Tue, 05 December 2017 23:11 UTC

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From: Grant Taylor <gtaylor@tnetconsulting.net>
Organization: TNet Consulting
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Date: Tue, 05 Dec 2017 16:05:59 -0700
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Subject: Re: [ietf-dkim] Mailsploit
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On 12/05/2017 03:52 PM, Pawel Lesnikowski wrote:
> encoded-words are simply not permitted inside email addresses. MUA 
> shouldn't attempt to decode this at all.

Perhaps they shouldn't attempt to decode it per say.

I think they should attempt to detect the presence of invalid characters 
and act accordingly.

> Attempting to decode is the first problem, incorrectly handling null 
> terminators and new lines is the second issue.

Okay.

> MUAs simply don't expect new lines and null terminators there.

Isn't expecting something unexpected a tenant of security?

I.e. code defensively.

> DKIM works as expected, but as you said it may re-enforce an incorrect 
> assumption that email is from respected source.

:-/



-- 
Grant. . . .
unix || die


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