IETF Logo Mail Archive

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

Return-Path: <hkario@redhat.com>
X-Original-To: tls@ietfa.amsl.com
Delivered-To: tls@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 3A97F1271FD; Tue, 20 Mar 2018 05:52:24 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -4.201
X-Spam-Level:
X-Spam-Status: No, score=-4.201 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, SPF_PASS=-0.001, T_RP_MATCHES_RCVD=-0.01, T_SPF_HELO_PERMERROR=0.01] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 3KOkkOktt4v5; Tue, 20 Mar 2018 05:52:22 -0700 (PDT)
Received: from mx1.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id B04CD127078; Tue, 20 Mar 2018 05:52:22 -0700 (PDT)
Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9F0CF4026129; Tue, 20 Mar 2018 12:52:21 +0000 (UTC)
Received: from pintsize.usersys.redhat.com (unknown [10.43.21.223]) by smtp.corp.redhat.com (Postfix) with ESMTP id D681B6F9E1; Tue, 20 Mar 2018 12:52:16 +0000 (UTC)
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
Message-ID: <7981509.2MgGW89sdW@pintsize.usersys.redhat.com>
In-Reply-To: <20180319225316.GP55745@kduck.kaduk.org>
References: <6112806.hxzZ6NivhB@pintsize.usersys.redhat.com> <6535335.hpFIu7S1IC@pintsize.usersys.redhat.com> <20180319225316.GP55745@kduck.kaduk.org>
MIME-Version: 1.0
Content-Type: multipart/signed; boundary="nextPart3211811.sFtsmfn93P"; micalg="pgp-sha512"; protocol="application/pgp-signature"
X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5
X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Tue, 20 Mar 2018 12:52:21 +0000 (UTC)
X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Tue, 20 Mar 2018 12:52:21 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'hkario@redhat.com' RCPT:''
Archived-At: <https://mailarchive.ietf.org/arch/msg/tls/RnUyCSRpBjCGarKBv30Ow79Pqms>
Subject: Re: [TLS] draft-ietf-tls-tls13-26 is vulnerable to externally set PSK identity enumeration
X-BeenThere: tls@ietf.org
X-Mailman-Version: 2.1.22
Precedence: list
List-Id: "This is the mailing list for the Transport Layer Security working group of the IETF." <tls.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/tls>, <mailto:tls-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/tls/>
List-Post: <mailto:tls@ietf.org>
List-Help: <mailto:tls-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/tls>, <mailto:tls-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 20 Mar 2018 12:52:24 -0000

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., Purkyňova 115, 612 00  Brno, Czech Republic

v2.23.0 | Report a Bug | By Email