{"id":"CVE-2026-43350","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: require a full NFS mode SID before reading mode bits\n\nparse_dacl() treats an ACE SID matching sid_unix_NFS_mode as an NFS\nmode SID and reads sid.sub_auth[2…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: require a full NFS mode SID before reading mode bits\n\nparse_dacl() treats an ACE SID matching sid_unix_NFS_mode as an NFS\nmode SID and reads sid.sub_auth[2…","severity":"high","cvss":7.6,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H","vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.4, < 6.6.136","linux_kernel >= 6.7, < 6.12.84","linux_kernel >= 6.13, < 6.18.25","linux_kernel >= 6.19, < 7.0.2"],"patched":["linux_kernel 7.0.2"],"published":"2026-05-08","updated":"2026-10-15","sourceUpdated":"2026-10-15T02:19:33.493","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-43350","references":[{"url":"https://git.kernel.org/stable/c/1592a6cd6f653f2d24572a6976c7a775b19f4940","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/23b54d6cc3ef30a51d984dc74364f24039ae2ecb","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2757ad3e4b6f9e0fed4c7739594e702abc5cab21","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/38a69f08ee82c450d3e4168707fff2e317dc3ff7","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8bd4cad3f458d11650d51c2d24b03fb1770ae6cc","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b53b8e98c23310294fc45fc686db5ee860311896","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c8eef12af1cc73031639ea7cf16e0b10e2536b0b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f8488c07bea2431ee12a6067d736578064fa46b4","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.00224,"epssPercentile":0.12082,"ingestedAt":"2026-10-15T03:30:12.874Z","slug":"CVE-2026-43350","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: require a full NFS mode SID before reading mode bits\n\nparse_dacl() treats an ACE SID matching sid_unix_NFS_mode as an NFS\nmode SID and reads sid.sub_auth[2] to recover the mode bits.\n\nThat assumes the ACE carries three subauthorities, but compare_sids()\nonly compares min(a, b) subauthorities.  A malicious server can return\nan ACE with num_subauth = 2 and sub_auth[] = {88, 3}, which still\nmatches sid_unix_NFS_mode and then drives the sub_auth[2] read four\nbytes past the end of the ACE.\n\nRequire num_subauth >= 3 before treating the ACE as an NFS mode SID.\nThis keeps the fix local to the special-SID mode path without changing\ncompare_sids() semantics for the rest of cifsacl.\n\n## Affected\n\n- `linux_kernel >= 5.4, < 6.6.136`\n- `linux_kernel >= 6.7, < 6.12.84`\n- `linux_kernel >= 6.13, < 6.18.25`\n- `linux_kernel >= 6.19, < 7.0.2`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 7.0.2`","depth":"twilight","depthScore":42,"depthScoreParts":{"impact":41.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}