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 88CA23D2FFB for ; Fri, 28 Aug 2026 06:52:50 +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=1787899974; cv=none; b=pK9XdJm/b/G60Biv2JNs53wtEzlWHclAvjLV4NogYgpCLKgOC5Z8w+No9Q2fRCLs/5XYiFcfJS4fbJo4ox7CDOVcSwR9CaE3N9EyUzx/iF2ffv7oUICdIfGaCXjX6w0daZtltoHDC96eIa2A1j9ChrqA3oGcN1iuZQnWTHn/eRc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787899974; c=relaxed/simple; bh=zrWDcK/hN0UzOUqUc0dti62HM+7N3YP4+Mug48ijjbY=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=T0CztaamOxJslO8VdNl1ldHUl3hChP/9Ec3wn/ay/Wh/hR+NlJ4ou1k+LnlhaMTdbVY5vquiqRTw6q0IQrVDg+Y8LK6q9QIARkSo+qDxlO8lIfXxTkVcDHihjyIfsSl/016TbPLkYXN9rRa+1waeGBjU+cy0WbpQq7lyLOxHuPg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=d1Holyi3; 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="d1Holyi3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0414B1F00A3A; Fri, 28 Aug 2026 06:52:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787899968; bh=pPYs+y9t90uemgih7v7ckTsMVoXRXwGaK1n9gcq8qYE=; h=From:To:Cc:Subject:Date:Reply-To; b=d1Holyi3Xr5EASv2o+As6NhmWVreXERPNkK2PT7fzu1NXzEZKH4OmwAQDZ7fXoXyz OWYxfEc0so83KEsE6pumL6NRDxtTgUqzQbmTV1FUCkq52giv8yL/4+JN8yhDqCiTVR OuI79eayM2OnanF0tzOLT4QYvMJaVB/YW47yyIOU= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-80673: ntfs: bound the look-ahead attribute-list entry in ntfs_external_attr_find() Date: Fri, 28 Aug 2026 08:49:50 +0200 Message-ID: <2026082848-CVE-2026-80673-fe8f@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=2826; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=vAprlbRqVOAiO+l4sk3e07awD/GNZuSVwPdH70y/E+k=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkT9QNly6dv63ilp6nsr7i3NcXSUKAyTK7VoojLc1lhu fcWjhMdsSwMgkwMsmKKLF+28RzdX3FI0cvQ9jTMHFYmkCEMXJwCMJFOJ4b5Ed/sjUz3mRZlldr/ ex9/SWfFKRc/hgWTzJJze3uVOP8Yn25uzs+eMntH4hsA 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: ntfs: bound the look-ahead attribute-list entry in ntfs_external_attr_find() When resolving an attribute lookup with a non-zero @lowest_vcn, ntfs_external_attr_find() peeks at the next $ATTRIBUTE_LIST entry to decide whether to keep searching, but bounds that not-yet-validated entry only with "(u8 *)next_al_entry + 6 < al_end" (which proves just bytes 0..6 are in range) and "(u8 *)next_al_entry + length <= al_end" with an attacker-controlled, non-8-aligned length. It then reads next_al_entry->lowest_vcn (an __le64 at offset 8) and the name at next_al_entry->name_offset, both of which can lie past al_end -- the exact end of the kvmalloc'd attribute-list buffer (allocated at the on-disk attr_list_size, no rounding). A crafted on-disk $ATTRIBUTE_LIST whose last entry sits a few bytes before al_end therefore yields a slab out-of-bounds read when the inode is read. Validate the look-ahead entry with ntfs_attr_list_entry_is_valid() (added in patch 1/3) before dereferencing lowest_vcn and the name, so the same fixed-header, length and name bounds the main attribute-list walk uses now guard this read too. The Linux kernel CVE team has assigned CVE-2026-80673 to this issue. Affected and fixed versions =========================== Issue introduced in 7.1 with commit 1e9ea7e04472d4e5e12e58c881eaacfb3e49b669 and fixed in 7.1.5 with commit 44885c9b45eb4082fb7f558590d84bb254a08e94 Issue introduced in 7.1 with commit 1e9ea7e04472d4e5e12e58c881eaacfb3e49b669 and fixed in 7.2 with commit 344b18f389f9934d59c7b0cf3d20541ea2e0da58 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-2026-80673 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: fs/ntfs/attrib.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/44885c9b45eb4082fb7f558590d84bb254a08e94 https://git.kernel.org/stable/c/344b18f389f9934d59c7b0cf3d20541ea2e0da58