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 D573B5013CA for ; Fri, 4 Sep 2026 15:59:57 +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=1788537599; cv=none; b=qE9lgjL9JBiD6I586BOfpfvrVaOit+MIyOh2hHtiRtP3AuQ5HYu4HMpwEDxZ3U7PBCyscXroi4K+zA+9PVHpnhQV7TG6Jd3moeuJnJhGAfocLGF6MsE5YuLg8WCpXxQ/wJNut/rGAra7zkhXB4u6GOaTzkYeJQs2ApsL7iGP2kI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788537599; c=relaxed/simple; bh=rVkS8NsdqXa21+/WXq1kL7sB+NosTj5ULLGYxv0o1rQ=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=L1/J98T6L3MHErAUV0IaqMdR3F4KglprdeYl0IoyWkxOS59EO37l6al86kbpo3QPlSgm/yfAVK+S6Otw/A3DO/NI6pUciBAQw2HlB8w9/V6zgdUlEBY2QZngotozEqiaE7y4Xq/q1ZnOpVMcmU30JE0pN9+1S+Yj/EmqtZ5JeGA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=vCEE/pCJ; 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="vCEE/pCJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B77471F01571; Fri, 4 Sep 2026 15:59:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788537597; bh=kF+/la6Z8tzo3Vvrr2ZTx0NRM9M10QtvmtGNhRM4cB4=; h=From:To:Cc:Subject:Date:Reply-To; b=vCEE/pCJemyQINtDN6xlDkXquswkF8pRSHY/+4ndmUk1CSiKmSXGD5mDzHEfCQVBd 61DLZYL5WBqr3TzwdUP87pmGw3bJoesO2R1VcVBE6Qjhi7f4Mtd2QykPhsti0Gn1jw /9yIoNK5wTDaY/ZDbS+BfwVQcxMYw+8KGjDgPY0w= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-80844: xfrm: ah6: validate routing header segments_left Date: Fri, 4 Sep 2026 17:53:11 +0200 Message-ID: <2026090458-CVE-2026-80844-7754@gregkh> X-Mailer: git-send-email 2.55.0 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=4145; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=xR1D532M6Zpw1EMbjV1w7D0qMNGoyeLcLTwU276W5gc=; b=owGbwMvMwCRo6H6F97bub03G02pJDFmzXkY/OCMqcLrw7Ob24kkN5p57TQLtfKRKIy5wr0pVU Y6zqsntiGVhEGRikBVTZPmyjefo/opDil6Gtqdh5rAygQxh4OIUgInkKTHM0y9dvlE3+syeadm3 yh5OEtkt214uwbCgY9tK373SzSnlRwqL5VRvz6j9+aQIAA== 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: xfrm: ah6: validate routing header segments_left AH6 rearranges routing-header addresses before computing or verifying the ICV. ipv6_rearrange_rthdr() assumes that segments_left is not larger than the number of addresses described by the routing header's hdrlen field. That assumption does not hold for raw IPv6 HDRINCL packets. A packet with hdrlen equal to 2 describes one address, but can carry an arbitrary segments_left value. With segments_left equal to 255, the function moves its address pointer 4,064 bytes backwards and passes a 4,064-byte length to memmove(), resulting in an out-of-bounds access. Validate the invariant locally before modifying the routing header or performing any address-pointer arithmetic, and propagate malformed-header errors to the existing AH6 input and output error paths. The Linux kernel CVE team has assigned CVE-2026-80844 to this issue. Affected and fixed versions =========================== Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 5.10.269 with commit 2dc650956e4e163b879b3fb1027f9557abc5c985 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 5.15.220 with commit 48b0e36cf54358276ee7aa897034c973097d2bc9 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.1.187 with commit 1b7e066eabcc7d6d8f476c34739b45932f2f4c31 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.6.156 with commit f00df8500e5a36ba70d336fd34bd2152ea074e5f Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.12.108 with commit 1516e31ac458a738be485620579d8f7fb2700fcb Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.18.49 with commit 6733ae71268a27d598cfb3f3339a3c950b9b656d Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.1.13 with commit 0bf11081ad3753938a2b48723ce6298dbac743a1 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.2.3 with commit 46640c814f25f096b0b0045ca50e1b7030cd8a30 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.3-rc1 with commit 7bad4bda74dc4713f398d3b7624ff05478e3a568 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-2026-80844 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/ipv6/ah6.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/2dc650956e4e163b879b3fb1027f9557abc5c985 https://git.kernel.org/stable/c/48b0e36cf54358276ee7aa897034c973097d2bc9 https://git.kernel.org/stable/c/1b7e066eabcc7d6d8f476c34739b45932f2f4c31 https://git.kernel.org/stable/c/f00df8500e5a36ba70d336fd34bd2152ea074e5f https://git.kernel.org/stable/c/1516e31ac458a738be485620579d8f7fb2700fcb https://git.kernel.org/stable/c/6733ae71268a27d598cfb3f3339a3c950b9b656d https://git.kernel.org/stable/c/0bf11081ad3753938a2b48723ce6298dbac743a1 https://git.kernel.org/stable/c/46640c814f25f096b0b0045ca50e1b7030cd8a30 https://git.kernel.org/stable/c/7bad4bda74dc4713f398d3b7624ff05478e3a568