{"api_version":"1","generated_at":"2026-10-21T11:24:10+00:00","cve":"CVE-2026-98735","urls":{"html":"https://cve.report/CVE-2026-98735","api":"https://cve.report/api/cve/CVE-2026-98735.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98735","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98735"},"summary":{"title":"Bluetooth: hci_core: Serialize ACL scheduling with channel deletion","description":"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.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-18 16:17:27","updated_at":"2026-10-19 10:19:37"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/86e9708f9d19a7f1bd5dc9c1652d07707f79f5bd","name":"https://git.kernel.org/stable/c/86e9708f9d19a7f1bd5dc9c1652d07707f79f5bd","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/51f95ea451f25d7e3f048c0f438f04fa74688aae","name":"https://git.kernel.org/stable/c/51f95ea451f25d7e3f048c0f438f04fa74688aae","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4fda8f0abeea9929036446d89a476fb8298abcb0","name":"https://git.kernel.org/stable/c/4fda8f0abeea9929036446d89a476fb8298abcb0","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f4845ab191a4f686a5da481fbba90ed73bb693b0","name":"https://git.kernel.org/stable/c/f4845ab191a4f686a5da481fbba90ed73bb693b0","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98735","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98735","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3eff45eaf81780dad25c167bbaafa7d25ae407da 51f95ea451f25d7e3f048c0f438f04fa74688aae git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3eff45eaf81780dad25c167bbaafa7d25ae407da 86e9708f9d19a7f1bd5dc9c1652d07707f79f5bd git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3eff45eaf81780dad25c167bbaafa7d25ae407da 4fda8f0abeea9929036446d89a476fb8298abcb0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3eff45eaf81780dad25c167bbaafa7d25ae407da f4845ab191a4f686a5da481fbba90ed73bb693b0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3.3","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 3.3 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.113 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.56 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.10 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/bluetooth/hci_core.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"51f95ea451f25d7e3f048c0f438f04fa74688aae","status":"affected","version":"3eff45eaf81780dad25c167bbaafa7d25ae407da","versionType":"git"},{"lessThan":"86e9708f9d19a7f1bd5dc9c1652d07707f79f5bd","status":"affected","version":"3eff45eaf81780dad25c167bbaafa7d25ae407da","versionType":"git"},{"lessThan":"4fda8f0abeea9929036446d89a476fb8298abcb0","status":"affected","version":"3eff45eaf81780dad25c167bbaafa7d25ae407da","versionType":"git"},{"lessThan":"f4845ab191a4f686a5da481fbba90ed73bb693b0","status":"affected","version":"3eff45eaf81780dad25c167bbaafa7d25ae407da","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/bluetooth/hci_core.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"3.3"},{"lessThan":"3.3","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.113","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.56","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.10","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.113","versionStartIncluding":"3.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.56","versionStartIncluding":"3.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.10","versionStartIncluding":"3.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"3.3","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"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."}],"providerMetadata":{"dateUpdated":"2026-10-19T09:24:45.664Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/51f95ea451f25d7e3f048c0f438f04fa74688aae"},{"url":"https://git.kernel.org/stable/c/86e9708f9d19a7f1bd5dc9c1652d07707f79f5bd"},{"url":"https://git.kernel.org/stable/c/4fda8f0abeea9929036446d89a476fb8298abcb0"},{"url":"https://git.kernel.org/stable/c/f4845ab191a4f686a5da481fbba90ed73bb693b0"}],"title":"Bluetooth: hci_core: Serialize ACL scheduling with channel deletion","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98735","datePublished":"2026-10-18T15:47:13.062Z","dateReserved":"2026-09-25T10:25:14.367Z","dateUpdated":"2026-10-19T09:24:45.664Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-18 16:17:27","lastModifiedDate":"2026-10-19 10:19:37","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98735","Ordinal":"1","Title":"Bluetooth: hci_core: Serialize ACL scheduling with channel delet","CVE":"CVE-2026-98735","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98735","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"Bluetooth: hci_core: Serialize ACL scheduling with channel delet"}]}}}