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Re: [openpgp] OpenPGP SEIP downgrade attack

Peter Gutmann <pgut001@cs.auckland.ac.nz> Tue, 06 October 2015 01:52 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Werner Koch <wk@gnupg.org>, Jonas Magazinius <jonas.magazinius@assured.se>
Thread-Topic: [openpgp] OpenPGP SEIP downgrade attack
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Date: Tue, 06 Oct 2015 01:51:58 +0000
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Subject: Re: [openpgp] OpenPGP SEIP downgrade attack
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Werner Koch <wk@gnupg.org> writes:

>More important however is my remark that we need to get MDC deployed so 
>that we can issue an error for non MDC packets instead of just a warning.

We don't need to get it deployed, we need to get it replaced by encrypt-
then-MAC, with the whole handled in a manner where downgrade attacks aren't
possible.

Peter.

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