{"schema":"threatline.record/2","record":{"id":"CVE-2026-98735","aliases":[],"summary":"Bluetooth: hci_core: Serialize ACL scheduling with channel deletion","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_core: Serialize ACL scheduling with channel deletion\n\nhci_chan_sent() selects a channel under RCU but drops the read lock before\naccessing chan->conn and returning the channel. The ACL and LE schedulers\nthen use its packet queue and update its transmit counters without any\nprotection against channel deletion.\n\nAfter TX selects a channel and releases RCU, a disconnect command timeout\non the separate request workqueue can run hci_conn_failed() and\nl2cap_conn_del(). hci_chan_del() can then unlink the channel, complete\nsynchronize_rcu(), purge its queue and free it before TX resumes. This\ncauses use-after-free both in hci_chan_sent() and in its callers.\n\nKASAN reported:\n\n  BUG: KASAN: slab-use-after-free in hci_chan_sent+0x892/0x9b0\n  Workqueue: hci0 hci_tx_work\n  Call Trace:\n   hci_chan_sent+0x892/0x9b0\n   hci_tx_work+0x5e6/0xb70\n  Allocated by task 91:\n   hci_chan_create+0xe3/0x350\n   l2cap_conn_add.part.0+0x12/0xa30\n   l2cap_chan_connect+0x110d/0x1b60\n   l2cap_sock_connect+0x310/0x530\n  Freed by task 99:\n   hci_chan_del+0x11f/0x170\n   l2cap_conn_del+0x4f1/0x800\n   l2cap_connect_cfm+0x88c/0xd30\n   hci_conn_failed+0x150/0x250\n   hci_abort_conn_sync+0x3e3/0x800\n   hci_cmd_sync_run+0x7e/0xc0\n   hci_abort_conn+0x105/0x1f0\n   disconnect_sync+0x157/0x290\n   hci_cmd_sync_work+0x13c/0x290\n\nHold the existing device mutex across channel selection and transmission\nin both schedulers to serialize them with channel teardown. Keep timeout\nhandling outside the critical sections because hci_link_tx_to() acquires\nthe same mutex. This also permits the transmit path to sleep, unlike\nextending the RCU read-side critical section across packet submission.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98735","source_modified_at":"2026-10-21T12:56:11.181Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"3eff45eaf81780dad25c167bbaafa7d25ae407da","lessThan":"780affacd92977fd9b819bdc4f26a6832cb27fda","status":"affected","versionType":"git"},{"version":"3eff45eaf81780dad25c167bbaafa7d25ae407da","lessThan":"51f95ea451f25d7e3f048c0f438f04fa74688aae","status":"affected","versionType":"git"},{"version":"3eff45eaf81780dad25c167bbaafa7d25ae407da","lessThan":"86e9708f9d19a7f1bd5dc9c1652d07707f79f5bd","status":"affected","versionType":"git"},{"version":"3eff45eaf81780dad25c167bbaafa7d25ae407da","lessThan":"4fda8f0abeea9929036446d89a476fb8298abcb0","status":"affected","versionType":"git"},{"version":"3eff45eaf81780dad25c167bbaafa7d25ae407da","lessThan":"f4845ab191a4f686a5da481fbba90ed73bb693b0","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98735","source_modified_at":"2026-10-21T12:56:11.181Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"3.3","status":"affected"},{"version":"0","lessThan":"3.3","status":"unaffected","versionType":"semver"},{"version":"6.6.160","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.113","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.56","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.10","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-2026-98735","source_modified_at":"2026-10-21T12:56:11.181Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"780affacd92977fd9b819bdc4f26a6832cb27fda","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98735","source_modified_at":"2026-10-21T12:56:11.181Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"51f95ea451f25d7e3f048c0f438f04fa74688aae","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98735","source_modified_at":"2026-10-21T12:56:11.181Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"86e9708f9d19a7f1bd5dc9c1652d07707f79f5bd","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98735","source_modified_at":"2026-10-21T12:56:11.181Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"4fda8f0abeea9929036446d89a476fb8298abcb0","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":0.00168,"percentile":0.05723,"score_date":"2026-10-23"},"published_at":"2026-10-18T15:47:13.062Z","modified_at":"2026-10-21T12:56:11.181Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-98735","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-21T12:56:11.181Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-98735","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/780affacd92977fd9b819bdc4f26a6832cb27fda"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/51f95ea451f25d7e3f048c0f438f04fa74688aae"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/86e9708f9d19a7f1bd5dc9c1652d07707f79f5bd"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/4fda8f0abeea9929036446d89a476fb8298abcb0"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/f4845ab191a4f686a5da481fbba90ed73bb693b0"}],"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":"2026-10-21T12:56:11.181Z","content_hash":"7a82bd4f6bad0898c851d770d599baecc8a115026206a55b47b9fe6ae14ff4c4"}}