{"schema":"threatline.record/2","record":{"id":"CVE-2026-98581","aliases":[],"summary":"nfc: llcp: Fix list corruption / refcount desync in nfc_llcp_recv_dm()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfc: llcp: Fix list corruption / refcount desync in nfc_llcp_recv_dm()\n\nnfc_llcp_recv_dm() handles DM(NOBOUND)/DM(REJ) for a socket that is still\nlinked on local->connecting_sockets: it looks the socket up with\nnfc_llcp_connecting_sock_get(), sets sk->sk_state = LLCP_CLOSED and\nreturns, without taking the socket lock and without unlinking the socket\nfrom the connecting_sockets list.\n\nllcp_sock_release() selects the list to unlink from by sk_state: a socket\nin LLCP_CONNECTING is unlinked from connecting_sockets, otherwise from the\nsockets list.  Because recv_dm left the socket physically on\nconnecting_sockets but in the LLCP_CLOSED state, release() takes the else\nbranch and calls nfc_llcp_sock_unlink(&local->sockets, sk).  That runs\nsk_del_node_init() while holding sockets.lock, i.e. it removes the socket\nfrom the connecting_sockets hlist under the wrong lock.  A concurrent\nconnect() linking another socket onto connecting_sockets under\nconnecting_sockets.lock then mutates the same hlist unserialized, which\ncorrupts the list and desyncs the sk_add_node()/sk_del_node_init()\nsock_hold()/__sock_put() pairing.  An unprivileged local process holding\nLLCP sockets, with the DM supplied by the remote peer over an established\nLLCP link, can drive this to leak kernel sockets without bound (the\nmis-decrement goes through the non-freeing __sock_put() path, so the\nobject is never released), leading to memory exhaustion / DoS.\n\nThis is the same class of bug that was fixed in the sibling handler\nnfc_llcp_recv_cc() by commit b493ea2765cc (\"nfc: llcp: Fix use-after-free\nrace in nfc_llcp_recv_cc()\"); recv_dm did not receive the equivalent fix.\n\nFix it the same way: take lock_sock(), re-check that the socket is still\nhashed (release() may have won the race), and for the NOBOUND/REJ case\nunlink it from connecting_sockets before moving it to LLCP_CLOSED.  The\nunlink drops the connecting_sockets membership reference via\nsk_del_node_init(), leaving the socket unhashed, so the later\nnfc_llcp_sock_unlink() in llcp_sock_release() becomes a no-op and no\ndouble put occurs.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98581","source_modified_at":"2026-10-19T09:22:07.016Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"a69f32af86e389dd232b1bb2269e202c1bfcc60f","lessThan":"dd2d24add86b3b63cd87cf2feff98ae119ba19a6","status":"affected","versionType":"git"},{"version":"a69f32af86e389dd232b1bb2269e202c1bfcc60f","lessThan":"812731dd8511f5768f4ff279b3c18d85cd21da4b","status":"affected","versionType":"git"},{"version":"a69f32af86e389dd232b1bb2269e202c1bfcc60f","lessThan":"dba1d9c7134afcb4b1bfad8c1b1b3f0ab5189b08","status":"affected","versionType":"git"},{"version":"a69f32af86e389dd232b1bb2269e202c1bfcc60f","lessThan":"c1e9ed52a6697354366dddf190fbacee8ed2f7c5","status":"affected","versionType":"git"},{"version":"a69f32af86e389dd232b1bb2269e202c1bfcc60f","lessThan":"7fb2c0eeb79bfad64065f539a453138abd0edda6","status":"affected","versionType":"git"},{"version":"a69f32af86e389dd232b1bb2269e202c1bfcc60f","lessThan":"b94cf09720543cc34256c7aa88f8059cbe7c0419","status":"affected","versionType":"git"},{"version":"a69f32af86e389dd232b1bb2269e202c1bfcc60f","lessThan":"320a2ff49bdce3f9a437b9a9ff341ff27d3bdbf1","status":"affected","versionType":"git"},{"version":"a69f32af86e389dd232b1bb2269e202c1bfcc60f","lessThan":"bf1460acdf8cf5a07c819f59785d40f20d113099","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98581","source_modified_at":"2026-10-19T09:22:07.016Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"3.6","status":"affected"},{"version":"0","lessThan":"3.6","status":"unaffected","versionType":"semver"},{"version":"5.10.271","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.222","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.189","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.158","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.112","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.55","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.9","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-2026-98581","source_modified_at":"2026-10-19T09:22:07.016Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"812731dd8511f5768f4ff279b3c18d85cd21da4b","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98581","source_modified_at":"2026-10-19T09:22:07.016Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"7fb2c0eeb79bfad64065f539a453138abd0edda6","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98581","source_modified_at":"2026-10-19T09:22:07.016Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"320a2ff49bdce3f9a437b9a9ff341ff27d3bdbf1","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":0.0021,"percentile":0.10719,"score_date":"2026-10-23"},"published_at":"2026-10-18T15:18:54.696Z","modified_at":"2026-10-19T09:22:07.016Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-98581","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-19T09:22:07.016Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-98581","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/dd2d24add86b3b63cd87cf2feff98ae119ba19a6"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/812731dd8511f5768f4ff279b3c18d85cd21da4b"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/dba1d9c7134afcb4b1bfad8c1b1b3f0ab5189b08"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/c1e9ed52a6697354366dddf190fbacee8ed2f7c5"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/7fb2c0eeb79bfad64065f539a453138abd0edda6"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/b94cf09720543cc34256c7aa88f8059cbe7c0419"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/320a2ff49bdce3f9a437b9a9ff341ff27d3bdbf1"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/bf1460acdf8cf5a07c819f59785d40f20d113099"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-19T09:22:07.016Z","content_hash":"bd4bcf9bc331874d361d31e61485593c500b5172aaccbc8d28e8d083a7412169"}}