From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E1513368D74 for ; Sun, 18 Oct 2026 15:31:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792337489; cv=none; b=np2yU8otKalvH//Okj/E9HhJoGxUV74pgSGV92Or7y3uO1qlnPMcG6ft7gaCQYakGbUJdaIceB3sJ7/+e6aZX/yfUEmz7CaR6/Sfp65If3avrO1T99kS4cvbsjlWBLqCxitxZp2hrZ/ys+kmw1B6A8/mwuEfTZ/0PhinkXeH1cw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792337489; c=relaxed/simple; bh=fY81xeewEGhypEhob4Cd2WShbc2ScdJ0FTAmTh/m/f0=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=KLeQj63VlfH2ayYGmR8PLOo7SqmxwVw5w29xAMluXIY/PRTnyKJf40CHbaJVpfjcA2dFoiLpXSl3KfThCFqv2uaxwI16kOb5E9GhWfcYluYRjRkzjFYNjsjmNst4u+8az4HgFpMoaLelJTE0rk88a3q/loZ+2RmLLjxFEgE9nJM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=lyaOYKs9; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="lyaOYKs9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 39F591F000C4; Sun, 18 Oct 2026 15:31:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792337488; bh=pSFkfDLZplkuTiR5ecRqFr49VSvG5Pj07lchoBUiubo=; h=From:To:Cc:Subject:Date:Reply-To; b=lyaOYKs9bCkkYvWz5n3ssI6rVtQ9L7eVq6KN1+FzsRv/rNMt1bwvtJ22vMKicNFdz oTHoAlbAGKy6zdYx98jn2gn+q7qfV86kr7suLtVYdTs6BWAsq2E96LkvMuieI6jf1x m2Notqy7GwpSRcMsxzdlrzpTpC09j6ZOsx7Uuu2Y= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-98586: sctp: hold asoc or transport before mod_timer() in timer handlers Date: Sun, 18 Oct 2026 17:17:30 +0200 Message-ID: <2026101835-CVE-2026-98586-ae30@gregkh> X-Mailer: git-send-email 2.56.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3805; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=CDme772uduaKagcZF6u5pmPNnT22sSya7mqUPgsdPBE=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlXHk1fI9nif4NlbvgtmaKJb2fsFvq6tr2XM2+GXsnds k45jr68jlgWBkEmBlkxRZYv23iO7q84pOhlaHsaZg4rE8gQBi5OAZjIjZ8M8yMmz018JrT75as6 KaH02oJ2h8N3OxjmilXsWiFrWD3L1G2u2u/X3vfkSwQ+AAA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: sctp: hold asoc or transport before mod_timer() in timer handlers Take the association or transport reference before rearming a timer in the timer handlers. The existing code calls mod_timer() before taking the reference needed by the rearmed timer without holding the sock lock. This creates a race with timer cleanup: if the timer is deleted after mod_timer() returns but before the reference is taken, the cleanup path can drop the timer's reference and destroy the transport or association. The timer handler then takes a reference on the already freed object and eventually drops it, causing a refcount underflow. Hold the object before mod_timer() and drop the reference if mod_timer() reports that the timer was already pending in timer handlers. Apply the same ordering to the proto-unreachable path, which can rearm a transport timer outside the timer handlers without holding the sock lock. The Linux kernel CVE team has assigned CVE-2026-98586 to this issue. Affected and fixed versions =========================== Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 5.15.222 with commit f7dea7eaea20fe9b80f8f77ba44d02b4a17f8050 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.1.189 with commit f9d929026d487a988bfa12c065f892e823e5b6ab Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.6.158 with commit 9d3d39da054476e7aa05cd877b93ca73a9a77434 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.12.112 with commit 27c51a9b55b227309161c903f9ecfbf022516bc2 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.18.55 with commit d18cb8fd1b6ba95c85de644203cfe1b071ff0c0f Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.2.9 with commit 35bf3b23c9a871f44c1453d85f8332be4e088dda Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.3-rc5 with commit cae23ae3f7887a1cf8a75da38edcebeef695040f Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-98586 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: net/sctp/input.c net/sctp/sm_sideeffect.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/f7dea7eaea20fe9b80f8f77ba44d02b4a17f8050 https://git.kernel.org/stable/c/f9d929026d487a988bfa12c065f892e823e5b6ab https://git.kernel.org/stable/c/9d3d39da054476e7aa05cd877b93ca73a9a77434 https://git.kernel.org/stable/c/27c51a9b55b227309161c903f9ecfbf022516bc2 https://git.kernel.org/stable/c/d18cb8fd1b6ba95c85de644203cfe1b071ff0c0f https://git.kernel.org/stable/c/35bf3b23c9a871f44c1453d85f8332be4e088dda https://git.kernel.org/stable/c/cae23ae3f7887a1cf8a75da38edcebeef695040f