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Re: [openpgp] New fingerprint: to v5 or not to v5

Werner Koch <wk@gnupg.org> Fri, 18 September 2015 12:25 UTC

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From: Werner Koch <wk@gnupg.org>
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Subject: Re: [openpgp] New fingerprint: to v5 or not to v5
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On Fri, 18 Sep 2015 00:05, vedaal@nym.hush.com said:
> would probably also become viable for subkeys as well, and it might be
> possible for an attacker to generate a subkey with a collision for the
> cross-certifying signature, and be able to graft a false subkey onto a

You mean the back signatures (Primary Key Binding Signature), right?
They are done directly on the key material and not on the fingerprint.
Thus back signatures can be updated to SHA-256 without problems.


Shalom-Salam,

   Werner

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