{"schema":"threatline.record/2","record":{"id":"CVE-2026-98870","aliases":[],"summary":"ksmbd: remove stale channels from all sessions on teardown","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: remove stale channels from all sessions on teardown\n\nksmbd_sessions_deregister() removes a connection's channels from other\nsessions' channel lists only while conn->binding is still set:\n\n\tif (conn->binding) {\n\t\thash_for_each_safe(sessions_table, ...)\n\t\t\tksmbd_chann_del(conn, sess);\n\t}\n\nconn->binding is a transient flag: it is cleared once a binding\nSESSION_SETUP completes, and also by a subsequent non-binding\nSESSION_SETUP on the same connection (a reauthentication on a bound\nchannel, or a new SessionId==0 setup). A connection that has bound a\nchannel into another session's ksmbd_chann_list and then clears\nconn->binding leaves that channel behind when it disconnects: the\nchannel, whose chann->conn points at the now freed struct ksmbd_conn,\nstays on the owner session's list.\n\nWhen the owning connection later tears down, the second loop\ndereferences the stale channel:\n\n\txa_for_each(&sess->ksmbd_chann_list, chann_id, chann)\n\t\tif (chann->conn != conn)\n\t\t\tksmbd_conn_set_exiting(chann->conn);   /* freed */\n\nwhich is a use-after-free write into the freed ksmbd_conn (the same\nstale channel is also walked by show_proc_session() through /proc). The\nsession is leaked as well, because its channel list never empties.\n\nRemove the conn->binding gate so a connection always removes its\nchannels from every session on teardown.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98870","source_modified_at":"2026-10-23T11:37:07.113Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Linux","vendor":"Linux","versions":[{"version":"b1b6ed903a6e2b3505a48706bcd499b447ef9e44","lessThan":"f8200bb4994e65a2e5c5b314789eeae39078619d","status":"affected","versionType":"git"},{"version":"47b018dba6ec7ebf403fd2d1e713bc7acc9bbb23","lessThan":"9cd6d714d3ca0cff296542dc989696884e41970f","status":"affected","versionType":"git"},{"version":"9ef4dfd5edbd02f4bf10cd420a30896093d98a67","lessThan":"b145f9b56c87f9c23ad5464ab0844dbc1de12b36","status":"affected","versionType":"git"},{"version":"5a5b0b7a01fe19b383b3c046546b5ae30c1a7d71","lessThan":"a15cae16f4432a5ad919ee633e31b07178492955","status":"affected","versionType":"git"},{"version":"faf8578c77f3d846aca9cd882c293e03eafcc6df","lessThan":"b10665730fbf6b5e45fe422badcbbc3f0df96ef5","status":"affected","versionType":"git"},{"version":"e632f21a8bc0c59abc4960482836ac3782db93c0","status":"affected","versionType":"git"},{"version":"5.15.222","lessThan":"5.16","status":"affected","versionType":"semver"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98870","source_modified_at":"2026-10-23T11:37:07.113Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Linux","vendor":"Linux","versions":[],"defaultStatus":"unaffected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98870","source_modified_at":"2026-10-23T11:37:07.113Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"9cd6d714d3ca0cff296542dc989696884e41970f","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98870","source_modified_at":"2026-10-23T11:37:07.113Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"5.16","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":null,"percentile":null,"score_date":null},"published_at":"2026-10-23T11:37:07.113Z","modified_at":"2026-10-23T11:37:07.113Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-98870","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23T11:37:07.113Z"}],"sources":["CVE List"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/f8200bb4994e65a2e5c5b314789eeae39078619d"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/9cd6d714d3ca0cff296542dc989696884e41970f"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/b145f9b56c87f9c23ad5464ab0844dbc1de12b36"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/a15cae16f4432a5ad919ee633e31b07178492955"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/b10665730fbf6b5e45fe422badcbbc3f0df96ef5"}],"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":"2026-10-23T11:37:07.113Z","content_hash":"396b2c84b94bde8bb4127cb0be763beeaf840770a0d54a9ca8856b3f741f210a"}}