{"api_version":"1","generated_at":"2026-05-11T11:02:56+00:00","cve":"CVE-2026-43350","urls":{"html":"https://cve.report/CVE-2026-43350","api":"https://cve.report/api/cve/CVE-2026-43350.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-43350","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-43350"},"summary":{"title":"smb: client: require a full NFS mode SID before reading mode bits","description":"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] 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.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-08 14:16:45","updated_at":"2026-05-11 08:16:10"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.6","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H","baseScore":7.6,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"REQUIRED","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.6","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H","data":{"baseScore":7.6,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/c8eef12af1cc73031639ea7cf16e0b10e2536b0b","name":"https://git.kernel.org/stable/c/c8eef12af1cc73031639ea7cf16e0b10e2536b0b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b53b8e98c23310294fc45fc686db5ee860311896","name":"https://git.kernel.org/stable/c/b53b8e98c23310294fc45fc686db5ee860311896","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/38a69f08ee82c450d3e4168707fff2e317dc3ff7","name":"https://git.kernel.org/stable/c/38a69f08ee82c450d3e4168707fff2e317dc3ff7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2757ad3e4b6f9e0fed4c7739594e702abc5cab21","name":"https://git.kernel.org/stable/c/2757ad3e4b6f9e0fed4c7739594e702abc5cab21","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f8488c07bea2431ee12a6067d736578064fa46b4","name":"https://git.kernel.org/stable/c/f8488c07bea2431ee12a6067d736578064fa46b4","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-43350","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43350","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e2f8fbfb8d09c06decde162090fac3ee220aa280 b53b8e98c23310294fc45fc686db5ee860311896 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e2f8fbfb8d09c06decde162090fac3ee220aa280 c8eef12af1cc73031639ea7cf16e0b10e2536b0b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e2f8fbfb8d09c06decde162090fac3ee220aa280 38a69f08ee82c450d3e4168707fff2e317dc3ff7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e2f8fbfb8d09c06decde162090fac3ee220aa280 f8488c07bea2431ee12a6067d736578064fa46b4 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 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original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"43350","cve":"CVE-2026-43350","epss":"0.000180000","percentile":"0.049330000","score_date":"2026-05-10","updated_at":"2026-05-11 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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."}],"metrics":[{"cvssV3_1":{"baseScore":7.6,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H","version":"3.1"}}],"providerMetadata":{"dateUpdated":"2026-05-11T06:33:32.916Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/b53b8e98c23310294fc45fc686db5ee860311896"},{"url":"https://git.kernel.org/stable/c/c8eef12af1cc73031639ea7cf16e0b10e2536b0b"},{"url":"https://git.kernel.org/stable/c/38a69f08ee82c450d3e4168707fff2e317dc3ff7"},{"url":"https://git.kernel.org/stable/c/f8488c07bea2431ee12a6067d736578064fa46b4"},{"url":"https://git.kernel.org/stable/c/2757ad3e4b6f9e0fed4c7739594e702abc5cab21"}],"title":"smb: client: require a full NFS mode SID before reading mode bits","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-43350","datePublished":"2026-05-08T13:41:53.276Z","dateReserved":"2026-05-01T14:12:56.003Z","dateUpdated":"2026-05-11T06:33:32.916Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-08 14:16:45","lastModifiedDate":"2026-05-11 08:16:10","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H","baseScore":7.6,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"REQUIRED","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"HIGH"},"exploitabilityScore":2.8,"impactScore":4.7}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"43350","Ordinal":"1","Title":"smb: client: require a full NFS mode SID before reading mode bit","CVE":"CVE-2026-43350","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"43350","Ordinal":"1","NoteData":"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] 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.","Type":"Description","Title":"smb: client: require a full NFS mode SID before reading mode bit"}]}}}