[TLS] WG Consensus Call: Prohibit Key Share Reuse Between Connections

Sean Turner <sean@sn3rd.com> Mon, 23 March 2026 20:40 UTC

Return-Path: <sean@sn3rd.com>
X-Original-To: tls@mail2.ietf.org
Delivered-To: tls@mail2.ietf.org
Received: from localhost (localhost [127.0.0.1]) by mail2.ietf.org (Postfix) with ESMTP id D4005D031A49 for <tls@mail2.ietf.org>; Mon, 23 Mar 2026 13:40:36 -0700 (PDT)
X-Virus-Scanned: amavisd-new at ietf.org
X-Spam-Flag: NO
X-Spam-Score: -2.1
X-Spam-Level:
X-Spam-Status: No, score=-2.1 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: mail2.ietf.org (amavisd-new); dkim=pass (1024-bit key) header.d=sn3rd.com
Received: from mail2.ietf.org ([166.84.6.31]) by localhost (mail2.ietf.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id YWIYjNz3R0ER for <tls@mail2.ietf.org>; Mon, 23 Mar 2026 13:40:36 -0700 (PDT)
Received: from mail-qk1-x743.google.com (mail-qk1-x743.google.com [IPv6:2607:f8b0:4864:20::743]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by mail2.ietf.org (Postfix) with ESMTPS id 69D29D031A44 for <tls@ietf.org>; Mon, 23 Mar 2026 13:40:36 -0700 (PDT)
Received: by mail-qk1-x743.google.com with SMTP id af79cd13be357-8cfc085395fso319393585a.2 for <tls@ietf.org>; Mon, 23 Mar 2026 13:40:36 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sn3rd.com; s=google; t=1774298436; x=1774903236; darn=ietf.org; h=to:date:message-id:subject:mime-version:content-transfer-encoding :from:from:to:cc:subject:date:message-id:reply-to; bh=Si1SRVLc2eELcGOcmn67aHXb9PxqTYeoOvfMRdxXZXA=; b=B0wf/ESxkfph88/MzkfbKfpkY9plaRDD6P5lr3+9sQ+wgD6UF76Czcoj2opzYj/lER zUKf2DmV7l/yBoEeB1KrdhdhhIj3CqITa4yI/CRf43SEpw9VLEcL4RnEZT/nn6uIqSD8 DYz16VR3fJQz/N3sgzEMUXIwAUDk3OdrYZYtA=
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774298436; x=1774903236; h=to:date:message-id:subject:mime-version:content-transfer-encoding :from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=Si1SRVLc2eELcGOcmn67aHXb9PxqTYeoOvfMRdxXZXA=; b=FHxlZa70fJKRhrbKCi3Uha7qijYCJGz3IKzJ5feI3WzMR8AGh7aIriXBzWZT3vkKCs W0/hLiuRZwj+fCTINnp5N15NJiSeOGV4CwfCUiKvcdH1iy05LaxsiGGDBegtHm484AGi 6bK7u6e66m0PA1+dltQe23tl9WL4O98fe+l8o7aUKTB1sBz4K9HPyso0RzUj6LBmuEsl sOhlMdxrgC3VnD6OcP8wQFyAqzT2q5TYoCmoPXHPr8Lj+kMB+VY+02mQwuvwOKjfn1/i zVd1bRX7OAw6A+2xOrDE3uh+oqudNqE3oounysir0VFVkuQOXvQGoPfj8jZyJ77/MdOE +XOA==
X-Gm-Message-State: AOJu0Yx1rfKcl38Q9hT451HNQsNr3m2q6sKZsyjNGzz9HoCHDo2olEK8 eSxoLzIVDeAszOULfzyWoejGRPEoW9RQf5a0C3jqC1iWgD/2YHXSEudF7ZvNz3lGbj6H9ms1YkS PUm8nR8JP88X+
X-Gm-Gg: ATEYQzwK59cr4Cz+5qEGl2dm7p38xdLGVUxGr/wDq/+2PEgEmPxk538wmCAEftiG/Kq pB5uSeLeqsd50fH5ROeZNM13/he1gfWNbxWWJEA+6Mlr7y6TQRz+SuGROf3AS1YdQhvTNQFQWAp u9Pd0wEFDRZOVqUPBL9j9SAfp5qOanrgYBW2vfe8tD3NR9cxDdLK3SswJqX4vfdGWl12+wWrh8U SiUYnPa2zPqtLKl+1y+lfqhS37Cl3dpVfLSwGK85WAI1rIpRBVJRPDOoazIiTw/+DbeltiQQRzg fEAE1YzPiKp5eVINwdfkmE1nJQLq/NEO78uz9HIXDBZTtmeVoC7e4K5tPcVtAb/fw0dwBdnul2B +sXzsNW9KjODPHH3D2RZiPIfC0Mnj2+tHr3p6OYwn/Ix+3FLqRse/eXoG+B8e4x9XWumNxdgpWF aCPedIPpalz9lacERu2vZPuEkv/QhrYu49eCAOGNpEsaIl5/5cE5UFfL/aOTt2Sptdag==
X-Received: by 2002:a05:620a:458d:b0:8cd:8142:b7d3 with SMTP id af79cd13be357-8cfc80af0bemr2042694485a.72.1774298435714; Mon, 23 Mar 2026 13:40:35 -0700 (PDT)
Received: from smtpclient.apple ([2600:4040:2555:6800:999f:c16:701f:551c]) by smtp.gmail.com with ESMTPSA id af79cd13be357-8cfc90bb7f0sm879308485a.38.2026.03.23.13.40.35 for <tls@ietf.org> (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 23 Mar 2026 13:40:35 -0700 (PDT)
From: Sean Turner <sean@sn3rd.com>
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3864.400.21\))
Message-Id: <92B7449C-F212-4A14-8852-58F8432FF131@sn3rd.com>
Date: Mon, 23 Mar 2026 16:40:14 -0400
To: TLS List <tls@ietf.org>
X-Mailer: Apple Mail (2.3864.400.21)
Message-ID-Hash: HXF5M6I6MHNH6A7QVDG5OMV32CDCOXCM
X-Message-ID-Hash: HXF5M6I6MHNH6A7QVDG5OMV32CDCOXCM
X-MailFrom: sean@sn3rd.com
X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-tls.ietf.org-0; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header
X-Mailman-Version: 3.3.9rc6
Precedence: list
Subject: [TLS] WG Consensus Call: Prohibit Key Share Reuse Between Connections
List-Id: "This is the mailing list for the Transport Layer Security working group of the IETF." <tls.ietf.org>
Archived-At: <https://mailarchive.ietf.org/arch/msg/tls/HXlf6FvX4B6NmH0zeffiTiXCXw8>
List-Archive: <https://mailarchive.ietf.org/arch/browse/tls>
List-Help: <mailto:tls-request@ietf.org?subject=help>
List-Owner: <mailto:tls-owner@ietf.org>
List-Post: <mailto:tls@ietf.org>
List-Subscribe: <mailto:tls-join@ietf.org>
List-Unsubscribe: <mailto:tls-leave@ietf.org>

This message starts a two week consensus call on whether draft-ietf-tls-rfc8446bis should prohibit key share reuse between connections. ekr has already produced a PR; see [1]. Please let the list know whether you do or do not support this change by 6 April 2026. Please note that if you already replied in here:[2] there is no need to also reply to this thread unless you changed your mind.

Note that as draft-ietf-tls-rfc8446bis in currently in AUTH48, this may add some delay to its publication. We believe that any delay would be small because we already know there are outstanding PRs that needed to be worked.

TLS Chairs (Joe & Sean)

[1] https://github.com/tlswg/tls13-spec/pull/1410
[2] https://mailarchive.ietf.org/arch/msg/tls/jpSC_G9chvSpL34X7pH3oCKh6cE/