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 19:55 UTC

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Date: Fri, 15 Dec 2017 21:55:29 +0200
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: Tim Hollebeek <tim.hollebeek@digicert.com>
Cc: Andrei Popov <Andrei.Popov@microsoft.com>, "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 Fri, Dec 15, 2017 at 07:33:44PM +0000, Tim Hollebeek wrote:
> 
> However, servers are easier to upgrade than clients, which is why you see
> some of the server side support you mention.  I know CloudFlare in
> particular helped a lot of people cope with communicating with clients who
> had different certificate capabilities.  It isn't a bad thing that both
> approaches exist.

Also, it should be noted that the past two migrations needed to be
compatible with TLS 1.0 and 1.1, which have much less advanced
signature negotiation than TLS 1.2 (and 1.3).

However, there are enormous amount of very badly configured servers out
there, so it is doubtful how quickly things change.


-Ilari