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Re: [Acme] Signature misuse vulnerability in draft-barnes-acme-04

Ilari Liusvaara <ilari.liusvaara@elisanet.fi> Thu, 13 August 2015 14:52 UTC

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Date: Thu, 13 Aug 2015 17:51:55 +0300
From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
To: Phillip Hallam-Baker <phill@hallambaker.com>
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Cc: Richard Barnes <rlb@ipv.sx>, "acme@ietf.org" <acme@ietf.org>, Andrew Ayer <agwa@andrewayer.name>, Stephen Farrell <stephen.farrell@cs.tcd.ie>
Subject: Re: [Acme] Signature misuse vulnerability in draft-barnes-acme-04
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On Thu, Aug 13, 2015 at 10:27:09AM -0400, Phillip Hallam-Baker wrote:
> +1
> 
> I would much rather block the entire class of attacks rather than spend any
> time working out if there is a way to do this with ECC based keys.

FYI, one of the five proposals for CFRG signatures:
- One is definitely vulernable (and key-checking won't help).
- Two are definitely not vulernable.
- Two I don't know.

So good idea to just block the attack.


-Ilari

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