Re: [TLS] draft-ietf-tls-tls13-26 is vulnerable to externally set PSK identity enumeration

Hubert Kario <hkario@redhat.com> Tue, 20 March 2018 12:52 UTC

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From: Hubert Kario <hkario@redhat.com>
To: Benjamin Kaduk <kaduk@mit.edu>
Cc: Eric Rescorla <ekr@rtfm.com>, tls-chairs <tls-chairs@ietf.org>, TLS WG <tls@ietf.org>, The IESG <iesg@ietf.org>
Date: Tue, 20 Mar 2018 13:52:11 +0100
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Subject: Re: [TLS] draft-ietf-tls-tls13-26 is vulnerable to externally set PSK identity enumeration
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On Monday, 19 March 2018 23:53:16 CET Benjamin Kaduk wrote:
> On Mon, Mar 19, 2018 at 05:00:51PM +0100, Hubert Kario wrote:
> > On Sunday, 18 March 2018 16:27:34 CET Eric Rescorla wrote:
> > > After discussion with the chairs and the AD, I have opted to just add a
> > > section
> > > that explains the attack. I just merged that (but managed not to get it
> > > into -27
> > > due to fumble fingering).
> > 
> > If there is no consensus on the recommended fix for the issue, I wonder if
> > we shouldn't then soften the language in the section about PSK binder
> > handling, from SHOULD to MAY.
> 
> I think on the balance I am happier retaining SHOULD.
> 
> > Though, I'd say that the reference to that newly added section is
> > definitely missing.
> 
> I expect that can be done as an RFC Editor note or during AUTH48.
> 
> -Benjamin

https://github.com/tlswg/tls13-spec/pull/1189 filed as a reminder

-- 
Regards,
Hubert Kario
Senior Quality Engineer, QE BaseOS Security team
Web: www.cz.redhat.com
Red Hat Czech s.r.o., Purky┼łova 115, 612 00  Brno, Czech Republic