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Re: [openpgp] V5 Fingerprint again

Vincent Breitmoser <look@my.amazin.horse> Thu, 02 March 2017 11:41 UTC

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From: Vincent Breitmoser <look@my.amazin.horse>
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Subject: Re: [openpgp] V5 Fingerprint again
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I think we can go slightly further here for depreciation in implementation logic: if a primary key is self signed with a stronger algorithm, a sha1 signature can be considered a security error. This avoids a downgrade scenario and catches misconfigurations but should have little potential for false positives.

The only scenario I can think of where this heuristic is off, is when the sender doesn't create their key themselves and isn't itself capable of stronger hashes. Not sure if that ever happens? 

 - V

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