{"api_version":"1","generated_at":"2026-05-11T11:02:39+00:00","cve":"CVE-2026-43391","urls":{"html":"https://cve.report/CVE-2026-43391","api":"https://cve.report/api/cve/CVE-2026-43391.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-43391","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-43391"},"summary":{"title":"nsfs: tighten permission checks for handle opening","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnsfs: tighten permission checks for handle opening\n\nEven privileged services should not necessarily be able to see other\nprivileged service's namespaces so they can't leak information to each\nother. 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Use may_see_all_namespaces() helper that centralizes this policy\nuntil the nstree adapts."}],"metrics":[{"cvssV3_1":{"baseScore":8.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","version":"3.1"}}],"providerMetadata":{"dateUpdated":"2026-05-11T06:34:07.262Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/1797ee11451f1b2be69863a9f5bd43b948813fdf"},{"url":"https://git.kernel.org/stable/c/d2324a9317f00013facb0ba00b00440e19d2af5e"}],"title":"nsfs: tighten permission checks for handle opening","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-43391","datePublished":"2026-05-08T14:21:36.012Z","dateReserved":"2026-05-01T14:12:56.007Z","dateUpdated":"2026-05-11T06:34:07.262Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-08 15:16:50","lastModifiedDate":"2026-05-11 08:16:12","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":2,"impactScore":6}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"43391","Ordinal":"1","Title":"nsfs: tighten permission checks for handle opening","CVE":"CVE-2026-43391","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"43391","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnsfs: tighten permission checks for handle opening\n\nEven privileged services should not necessarily be able to see other\nprivileged service's namespaces so they can't leak information to each\nother. Use may_see_all_namespaces() helper that centralizes this policy\nuntil the nstree adapts.","Type":"Description","Title":"nsfs: tighten permission checks for handle opening"}]}}}