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Re: [openpgp] Followup on fingerprints

Werner Koch <wk@gnupg.org> Tue, 04 August 2015 06:45 UTC

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From: Werner Koch <wk@gnupg.org>
To: Vincent Breitmoser <look@my.amazin.horse>
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Mail-Followup-To: Vincent Breitmoser <look@my.amazin.horse>, IETF OpenPGP <openpgp@ietf.org>
Date: Tue, 04 Aug 2015 08:44:27 +0200
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Subject: Re: [openpgp] Followup on fingerprints
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On Tue,  4 Aug 2015 04:42, look@my.amazin.horse said:

> And the actual attack is "slightly weaker non-repudiation"?

... when using a truncated fingerprint.

Why should anyone truncate a fingerprint from 20 bytes to 13 bytes?
This is an arbitrary value in between the known weak 8 byte keyids and
the full 20 byte fingerprints for which we expect that in our lifetime
collisions can be created.


Shalom-Salam,

   Werner

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Die Gedanken sind frei.  Ausnahmen regelt ein Bundesgesetz.

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