{"schema":"threatline.record/2","record":{"id":"CVE-2026-97609","aliases":[],"summary":"netfilter: cttimeout: prevent UAF during module unload","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: cttimeout: prevent UAF during module unload\n\nnf_ct_set_timeout() protects the timeout hook dereference and policy lookup\nwith rcu_read_lock(). cttimeout_exit(), however, unregisters the per-net\noperations before it clears the hook.\n\nThis allows the following interleaving:\n\n  CPU 0                              CPU 1\n  cttimeout_exit()                   nf_ct_set_timeout()\n    unregister_pernet_subsys()         rcu_read_lock()\n      kfree(pernet)                     h = nf_ct_timeout_hook\n                                        h->timeout_find_get()\n                                          nfct_timeout_pernet()\n\nThe hook still points to ctnl_timeout_find_get() when CPU 1 looks up the\nalready freed per-net timeout list. KASAN reported:\n\n  BUG: KASAN: slab-use-after-free in ctnl_timeout_find_get\n  Read of size 8 by task poc/90\n  Call Trace:\n   ctnl_timeout_find_get+0x271/0x2a0 [nfnetlink_cttimeout]\n   nf_ct_set_timeout+0x7b/0x3c0\n   xt_ct_tg_check+0x724/0xb20\n   xt_check_target+0x234/0xa90\n   do_ipt_set_ctl+0x570/0x1270\n  Allocated by task 89:\n   __kmalloc_noprof+0x16e/0x460\n   ops_init+0x6d/0x420\n   register_pernet_operations+0x2f6/0x670\n  Freed by task 91:\n   kfree+0x131/0x390\n   ops_undo_list+0x3d4/0x730\n   unregister_pernet_operations+0x232/0x490\n   unregister_pernet_subsys+0x1c/0x30\n   cttimeout_exit+0x52/0x970 [nfnetlink_cttimeout]\n\nClear the hook and wait for existing readers before unregistering the\nper-net operations. This blocks new policy lookups and ensures readers that\nobserved the hook finish before the per-net storage is freed.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97609","source_modified_at":"2026-10-21T12:53:26.912Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"ebfbe67568a734a449203097b02c4ab884257535","lessThan":"f664e06699829a31e95675a6864655a6c5f9904f","status":"affected","versionType":"git"},{"version":"ebfbe67568a734a449203097b02c4ab884257535","lessThan":"73f353bec62509c776184e49a031c6145cec0d05","status":"affected","versionType":"git"},{"version":"ebfbe67568a734a449203097b02c4ab884257535","lessThan":"a7fdd86c386b7f7cc72a126389c2cdb55d035221","status":"affected","versionType":"git"},{"version":"ebfbe67568a734a449203097b02c4ab884257535","lessThan":"1f69c570a73f2dedf75ea5166d47622d5fa958c1","status":"affected","versionType":"git"},{"version":"ebfbe67568a734a449203097b02c4ab884257535","lessThan":"fec9b1de0d02de8dafa3cc344bcb91cf28660643","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97609","source_modified_at":"2026-10-21T12:53:26.912Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"5.13","status":"affected"},{"version":"0","lessThan":"5.13","status":"unaffected","versionType":"semver"},{"version":"6.6.160","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.112","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.53","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.7","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97609","source_modified_at":"2026-10-21T12:53:26.912Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"73f353bec62509c776184e49a031c6145cec0d05","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97609","source_modified_at":"2026-10-21T12:53:26.912Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"1f69c570a73f2dedf75ea5166d47622d5fa958c1","basis":"first unaffected version stated in the CVE record"}],"cvss":7,"severity":"High","kev":{"listed":false},"epss":{"probability":0.0014,"percentile":0.0309,"score_date":"2026-10-23"},"published_at":"2026-09-25T10:22:19.627Z","modified_at":"2026-10-21T12:53:26.912Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-97609","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-21T12:53:26.912Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-97609","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/f664e06699829a31e95675a6864655a6c5f9904f"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/73f353bec62509c776184e49a031c6145cec0d05"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/a7fdd86c386b7f7cc72a126389c2cdb55d035221"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/1f69c570a73f2dedf75ea5166d47622d5fa958c1"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/fec9b1de0d02de8dafa3cc344bcb91cf28660643"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-21T12:53:26.912Z","content_hash":"45c6c93a3499b416f0717835bc1e00801340d46e470d46d73ac28452ef4f9a5d"}}