{"api_version":"1","generated_at":"2026-04-10T00:19:14+00:00","cve":"CVE-2026-23405","urls":{"html":"https://cve.report/CVE-2026-23405","api":"https://cve.report/api/cve/CVE-2026-23405.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-23405","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-23405"},"summary":{"title":"apparmor: fix: limit the number of levels of policy namespaces","description":"In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: fix: limit the number of levels of policy namespaces\n\nCurrently the number of policy namespaces is not bounded relying on\nthe user namespace limit. 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the Linux kernel, the following vulnerability has been resolved:\n\napparmor: fix: limit the number of levels of policy namespaces\n\nCurrently the number of policy namespaces is not bounded relying on\nthe user namespace limit. However policy namespaces aren't strictly\ntied to user namespaces and it is possible to create them and nest\nthem arbitrarily deep which can be used to exhaust system resource.\n\nHard cap policy namespaces to the same depth as user namespaces."}],"providerMetadata":{"dateUpdated":"2026-04-01T08:36:35.697Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/3f8699b3ee0c04b4b9bc27b82cd89a40e81e1d2e"},{"url":"https://git.kernel.org/stable/c/853ce31ca72097d23991a06876a2ccb5cb64b603"},{"url":"https://git.kernel.org/stable/c/d42b2b6bb77ca40ee34ab74ad79305840b5f315d"},{"url":"https://git.kernel.org/stable/c/7b6495ead2c611647f6b11441a852324e3eb8616"},{"url":"https://git.kernel.org/stable/c/306039414932c80f8420695a24d4fe10c84ccfb2"}],"title":"apparmor: fix: limit the number of levels of policy namespaces","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-23405","datePublished":"2026-04-01T08:36:35.697Z","dateReserved":"2026-01-13T15:37:46.012Z","dateUpdated":"2026-04-01T08:36:35.697Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-04-01 09:16:16","lastModifiedDate":"2026-04-01 14:23:37","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"23405","Ordinal":"1","Title":"apparmor: fix: limit the number of levels of policy namespaces","CVE":"CVE-2026-23405","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"23405","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: fix: limit the number of levels of policy namespaces\n\nCurrently the number of policy namespaces is not bounded relying on\nthe user namespace limit. However policy namespaces aren't strictly\ntied to user namespaces and it is possible to create them and nest\nthem arbitrarily deep which can be used to exhaust system resource.\n\nHard cap policy namespaces to the same depth as user namespaces.","Type":"Description","Title":"apparmor: fix: limit the number of levels of policy namespaces"}]}}}