Re: [TLS] WGLC for draft-ietf-tls-md5-sha1-deprecate

Alessandro Ghedini <alessandro@ghedini.me> Thu, 23 April 2020 17:47 UTC

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Date: Thu, 23 Apr 2020 18:47:18 +0100
From: Alessandro Ghedini <alessandro@ghedini.me>
To: Karthik Bhargavan <karthikeyan.bhargavan@inria.fr>
Cc: Ilari Liusvaara <ilariliusvaara@welho.com>, tls@ietf.org
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Subject: Re: [TLS] WGLC for draft-ietf-tls-md5-sha1-deprecate
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On Sat, Nov 23, 2019 at 05:32:36PM +0100, Karthik Bhargavan wrote:
> This is a bit of a shameless plug, but I think it is important to cite papers that show that the use of weak hash functions for TLS signatures is actually exploitable.
> 
> As far as I know, the last round of deprecating MD5 in TLS signatures was triggered by the SLOTH attack:
> 
> https://www.mitls.org/pages/attacks/SLOTH
> 
> The associated paper explains how weak hash functions can allow an attacker to break protocols like TLS, SSH, etc.
> 
> https://www.mitls.org/downloads/transcript-collisions.pdf
> 
> This probably deserves to be added to the references of this draft.
> 
> @inproceedings{BhargavanL16,
>   author    = {Karthikeyan Bhargavan and Gaetan Leurent},
>   title     = {Transcript Collision Attacks: Breaking Authentication in TLS, IKE, and SSH},
>   booktitle = {Proceedings of the {ISOC} Network and Distributed System Security Symposium ({NDSS} '16)},
>   month     = {Feb},
>   year      = {2016},
>   url       = {
> http://www.mitls.org/downloads/transcript-collisions.pdf
> }
> }

Thanks, I made https://github.com/tlswg/draft-ietf-tls-md5-sha1-deprecate/pull/6
to add a reference to this paper as well.

Cheers