{"id":"CVE-2026-80845","state":"PUBLISHED","title":"xfrm: avoid lock inversion in nat keepalive work","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: avoid lock inversion in nat keepalive work\n\nnat_keepalive_work() walks the state table while xfrm_state_walk()\nholds net->xfrm.xfrm_state_lock. Its callback then acquires x->lock,\nwhich conflicts with the delete path taking the same locks in reverse\norder via xfrm_state_delete() and __xfrm_state_delete(). This creates\nan AB-BA deadlock that is reported by lockdep when a NAT keepalive\nworker races with SA deletion.\n\nFix this by splitting the keepalive walk into two phases. First,\ncollect the candidate states while the walk holds xfrm_state_lock and\ntake a reference on each state. Then, after the walk completes, process\neach collected state and acquire x->lock without nesting it under\nxfrm_state_lock.","publishedAt":"2026-09-04T15:54:55.489Z","updatedAt":"2026-10-19T08:44:39.455Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae","status":"affected","lessThan":"ea09210462316e5235a25eccb11ad0708d86615e","versionType":"git"},{"version":"f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae","status":"affected","lessThan":"5c86c895d1cac81a71ead3005084c6265cf6a7a5","versionType":"git"},{"version":"f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae","status":"affected","lessThan":"89ef3a2e1e4682ab82b0455ce113f8c39fb9e50d","versionType":"git"},{"version":"f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae","status":"affected","lessThan":"a9fa05b7a1246797748d15771052639e0d3cabf1","versionType":"git"},{"version":"f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae","status":"affected","lessThan":"763fe700b7c58ad64fe5202c5638848244dd4127","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xfrm/xfrm_nat_keepalive.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.11","versionType":"semver"},{"version":"6.12.108","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.49","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.13","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2.3","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xfrm/xfrm_nat_keepalive.c"]}],"references":["https://git.kernel.org/stable/c/ea09210462316e5235a25eccb11ad0708d86615e","https://git.kernel.org/stable/c/5c86c895d1cac81a71ead3005084c6265cf6a7a5","https://git.kernel.org/stable/c/89ef3a2e1e4682ab82b0455ce113f8c39fb9e50d","https://git.kernel.org/stable/c/a9fa05b7a1246797748d15771052639e0d3cabf1","https://git.kernel.org/stable/c/763fe700b7c58ad64fe5202c5638848244dd4127"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:07.220Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/80xxx/CVE-2026-80845.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80845","state":"PUBLISHED","datePublished":"2026-09-04T15:54:55.489Z","dateUpdated":"2026-10-19T08:44:39.455Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-26T14:34:25.797Z"},"containers":{"cna":{"title":"xfrm: avoid lock inversion in nat keepalive work","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: avoid lock inversion in nat keepalive work\n\nnat_keepalive_work() walks the state table while xfrm_state_walk()\nholds net->xfrm.xfrm_state_lock. Its callback then acquires x->lock,\nwhich conflicts with the delete path taking the same locks in reverse\norder via xfrm_state_delete() and __xfrm_state_delete(). This creates\nan AB-BA deadlock that is reported by lockdep when a NAT keepalive\nworker races with SA deletion.\n\nFix this by splitting the keepalive walk into two phases. First,\ncollect the candidate states while the walk holds xfrm_state_lock and\ntake a reference on each state. Then, after the walk completes, process\neach collected state and acquire x->lock without nesting it under\nxfrm_state_lock."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae","status":"affected","lessThan":"ea09210462316e5235a25eccb11ad0708d86615e","versionType":"git"},{"version":"f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae","status":"affected","lessThan":"5c86c895d1cac81a71ead3005084c6265cf6a7a5","versionType":"git"},{"version":"f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae","status":"affected","lessThan":"89ef3a2e1e4682ab82b0455ce113f8c39fb9e50d","versionType":"git"},{"version":"f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae","status":"affected","lessThan":"a9fa05b7a1246797748d15771052639e0d3cabf1","versionType":"git"},{"version":"f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae","status":"affected","lessThan":"763fe700b7c58ad64fe5202c5638848244dd4127","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xfrm/xfrm_nat_keepalive.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.11","versionType":"semver"},{"version":"6.12.108","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.49","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.13","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2.3","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xfrm/xfrm_nat_keepalive.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/ea09210462316e5235a25eccb11ad0708d86615e"},{"url":"https://git.kernel.org/stable/c/5c86c895d1cac81a71ead3005084c6265cf6a7a5"},{"url":"https://git.kernel.org/stable/c/89ef3a2e1e4682ab82b0455ce113f8c39fb9e50d"},{"url":"https://git.kernel.org/stable/c/a9fa05b7a1246797748d15771052639e0d3cabf1"},{"url":"https://git.kernel.org/stable/c/763fe700b7c58ad64fe5202c5638848244dd4127"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:44:39.455Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.12.108"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.18.49"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"7.1.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"7.2.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}