{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-23405","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-01-13T15:37:46.012Z","datePublished":"2026-04-01T08:36:35.697Z","dateUpdated":"2026-05-11T22:06:16.436Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T22:06:16.436Z"},"descriptions":[{"lang":"en","value":"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."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["security/apparmor/include/policy_ns.h","security/apparmor/policy_ns.c"],"versions":[{"version":"c88d4c7b049e87998ac0a9f455aa545cc895ef92","lessThan":"6b396cc2f0365e684fc1d3547d18ef79fcee225d","status":"affected","versionType":"git"},{"version":"c88d4c7b049e87998ac0a9f455aa545cc895ef92","lessThan":"87d0cecc900e55d55fc4dbfb43ac93e269c7a5b3","status":"affected","versionType":"git"},{"version":"c88d4c7b049e87998ac0a9f455aa545cc895ef92","lessThan":"b1226e37eb3754d389721c135db6107db94c7a72","status":"affected","versionType":"git"},{"version":"c88d4c7b049e87998ac0a9f455aa545cc895ef92","lessThan":"3f8699b3ee0c04b4b9bc27b82cd89a40e81e1d2e","status":"affected","versionType":"git"},{"version":"c88d4c7b049e87998ac0a9f455aa545cc895ef92","lessThan":"853ce31ca72097d23991a06876a2ccb5cb64b603","status":"affected","versionType":"git"},{"version":"c88d4c7b049e87998ac0a9f455aa545cc895ef92","lessThan":"d42b2b6bb77ca40ee34ab74ad79305840b5f315d","status":"affected","versionType":"git"},{"version":"c88d4c7b049e87998ac0a9f455aa545cc895ef92","lessThan":"7b6495ead2c611647f6b11441a852324e3eb8616","status":"affected","versionType":"git"},{"version":"c88d4c7b049e87998ac0a9f455aa545cc895ef92","lessThan":"306039414932c80f8420695a24d4fe10c84ccfb2","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["security/apparmor/include/policy_ns.h","security/apparmor/policy_ns.c"],"versions":[{"version":"2.6.36","status":"affected"},{"version":"0","lessThan":"2.6.36","status":"unaffected","versionType":"semver"},{"version":"5.10.253","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.203","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.169","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.130","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.77","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.18","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"6.19.8","lessThanOrEqual":"6.19.*","status":"unaffected","versionType":"semver"},{"version":"7.0","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.36","versionEndExcluding":"5.10.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.36","versionEndExcluding":"5.15.203"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.36","versionEndExcluding":"6.1.169"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.36","versionEndExcluding":"6.6.130"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.36","versionEndExcluding":"6.12.77"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.36","versionEndExcluding":"6.18.18"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.36","versionEndExcluding":"6.19.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.36","versionEndExcluding":"7.0"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/6b396cc2f0365e684fc1d3547d18ef79fcee225d"},{"url":"https://git.kernel.org/stable/c/87d0cecc900e55d55fc4dbfb43ac93e269c7a5b3"},{"url":"https://git.kernel.org/stable/c/b1226e37eb3754d389721c135db6107db94c7a72"},{"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"}}}}