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Re: [TLS] A closer look at ROBOT, BB Attacks, timing attacks in general, and what we can do in TLS

Ilari Liusvaara <ilariliusvaara@welho.com> Fri, 15 December 2017 14:31 UTC

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Date: Fri, 15 Dec 2017 16:30:57 +0200
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: Colm MacCárthaigh <colm@allcosts.net>
Cc: Hanno Böck <hanno@hboeck.de>, "tls@ietf.org" <tls@ietf.org>
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Subject: Re: [TLS] A closer look at ROBOT, BB Attacks, timing attacks in general, and what we can do in TLS
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On Thu, Dec 14, 2017 at 05:05:37PM -0800, Colm MacCárthaigh wrote:

> But I do think the question
> is worth having an answer for. I think we *do* need to prepare for turning
> off AES, there's always a chance we might have to.

Even nastier dependency: SHA-2. If that breaks, currently both TLS 1.2
and 1.3 break. There are no alternatives defined.

Yes, sure SHA-2 has taken a lot of cryptoanalysis without serious
trouble (I think one reason for starting SHA-3 process was preceived
weakness in SHA-2, that later turned out not to be the case). 


-Ilari

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