Re: [Cfrg] A downside of deterministic DL signatures?

Daniel Kahn Gillmor <dkg@fifthhorseman.net> Thu, 31 July 2014 17:23 UTC

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Date: Thu, 31 Jul 2014 13:23:05 -0400
From: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
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To: Tony Arcieri <bascule@gmail.com>, Michael Hamburg <mike@shiftleft.org>
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Cc: Dan Brown <dbrown@certicom.com>, IRTF Crypto Forum Research Group <cfrg@irtf.org>
Subject: Re: [Cfrg] A downside of deterministic DL signatures?
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On 07/31/2014 01:08 PM, Tony Arcieri wrote:
> On Thu, Jul 31, 2014 at 12:40 AM, Michael Hamburg <mike@shiftleft.org>
> wrote:
> 
>> Indeed.  But collision attacks have also broken signature schemes *in
>> practice*, for example the Flame malware.
>>
> 
> Are there any other examples of collision attacks in the wild? Also note
> this attack required a nationstate-level effort.

sure:

  http://www.win.tue.nl/hashclash/rogue-ca/

and other instances from the same group, including the cheeky:

  http://www.win.tue.nl/hashclash/Nostradamus/

neither of these required nationstate-level effort, and they date back
to 2008.

	--dkg