{"id":"CVE-2026-45884","state":"PUBLISHED","title":"apparmor: avoid per-cpu hold underflow in aa_get_buffer","description":"In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: avoid per-cpu hold underflow in aa_get_buffer\n\nWhen aa_get_buffer() pulls from the per-cpu list it unconditionally\ndecrements cache->hold. If hold reaches 0 while count is still non-zero,\nthe unsigned decrement wraps to UINT_MAX. This keeps hold non-zero for a\nvery long time, so aa_put_buffer() never returns buffers to the global\nlist, which can starve other CPUs and force repeated kmalloc(aa_g_path_max)\nallocations.\n\nGuard the decrement so hold never underflows.","publishedAt":"2026-05-27T12:16:56.542Z","updatedAt":"2026-05-27T12:16:56.542Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ea9bae12d02819556db63348db8bd8441eb316f2","status":"affected","lessThan":"202824a1f89a9786c20a3d646a7c88d223abb1b2","versionType":"git"},{"version":"ea9bae12d02819556db63348db8bd8441eb316f2","status":"affected","lessThan":"80c334acc6d0bee8605a358a33e69b4aea1ffb92","versionType":"git"},{"version":"ea9bae12d02819556db63348db8bd8441eb316f2","status":"affected","lessThan":"4bcddd0f6b2e52b4c7b520e4d36a115caf5b7169","versionType":"git"},{"version":"ea9bae12d02819556db63348db8bd8441eb316f2","status":"affected","lessThan":"640cf2f09575c9dc344b3f7be2498d31e3923ead","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["security/apparmor/lsm.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.7","versionType":"semver"},{"version":"6.12.75","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.14","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.4","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["security/apparmor/lsm.c"]}],"references":["https://git.kernel.org/stable/c/202824a1f89a9786c20a3d646a7c88d223abb1b2","https://git.kernel.org/stable/c/80c334acc6d0bee8605a358a33e69b4aea1ffb92","https://git.kernel.org/stable/c/4bcddd0f6b2e52b4c7b520e4d36a115caf5b7169","https://git.kernel.org/stable/c/640cf2f09575c9dc344b3f7be2498d31e3923ead"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/45xxx/CVE-2026-45884.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-45884","state":"PUBLISHED","datePublished":"2026-05-27T12:16:56.542Z","dateUpdated":"2026-05-27T12:16:56.542Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-05-13T15:03:33.082Z"},"containers":{"cna":{"title":"apparmor: avoid per-cpu hold underflow in aa_get_buffer","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: avoid per-cpu hold underflow in aa_get_buffer\n\nWhen aa_get_buffer() pulls from the per-cpu list it unconditionally\ndecrements cache->hold. If hold reaches 0 while count is still non-zero,\nthe unsigned decrement wraps to UINT_MAX. This keeps hold non-zero for a\nvery long time, so aa_put_buffer() never returns buffers to the global\nlist, which can starve other CPUs and force repeated kmalloc(aa_g_path_max)\nallocations.\n\nGuard the decrement so hold never underflows."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ea9bae12d02819556db63348db8bd8441eb316f2","status":"affected","lessThan":"202824a1f89a9786c20a3d646a7c88d223abb1b2","versionType":"git"},{"version":"ea9bae12d02819556db63348db8bd8441eb316f2","status":"affected","lessThan":"80c334acc6d0bee8605a358a33e69b4aea1ffb92","versionType":"git"},{"version":"ea9bae12d02819556db63348db8bd8441eb316f2","status":"affected","lessThan":"4bcddd0f6b2e52b4c7b520e4d36a115caf5b7169","versionType":"git"},{"version":"ea9bae12d02819556db63348db8bd8441eb316f2","status":"affected","lessThan":"640cf2f09575c9dc344b3f7be2498d31e3923ead","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["security/apparmor/lsm.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.7","versionType":"semver"},{"version":"6.12.75","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.14","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.4","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["security/apparmor/lsm.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/202824a1f89a9786c20a3d646a7c88d223abb1b2"},{"url":"https://git.kernel.org/stable/c/80c334acc6d0bee8605a358a33e69b4aea1ffb92"},{"url":"https://git.kernel.org/stable/c/4bcddd0f6b2e52b4c7b520e4d36a115caf5b7169"},{"url":"https://git.kernel.org/stable/c/640cf2f09575c9dc344b3f7be2498d31e3923ead"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-27T12:16:56.542Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"6.12.75"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"6.18.14"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"6.19.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}