{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98290", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.336Z", "datePublished": "2026-10-06T08:45:50.299Z", "dateUpdated": "2026-10-19T09:17:01.498Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:17:01.498Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: RFCOMM: avoid socket lock inversion in listener cleanup\n\nrfcomm_sock_cleanup_listen() closes unaccepted child sockets through\nrfcomm_sock_close(), which takes the child socket lock before\nrfcomm_dlc_close() acquires rfcomm_mutex. The RFCOMM worker takes these\nlocks in reverse order while handling connections and DLC state changes,\nso lockdep reports a possible deadlock.\n\nClose dequeued children without taking their socket lock. The accept queue\nowns a reference to each child, and bt_accept_dequeue() locks the child\nwhile unlinking it and clearing its parent pointer.\n\nDropping the child lock makes it important to prevent a concurrent\nrfcomm_connect_ind() from enqueueing a new child after cleanup observes an\nempty queue. Set a listening socket to BT_CLOSED while its lock is still\nheld, before dropping the lock and draining the queue. The state check in\nrfcomm_connect_ind() then rejects new children once cleanup starts." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:A - A Bluetooth peer drives both halves of this bug. Its RFCOMM SABM creates a child in rfcomm_connect_ind(), and its later DISC makes krfcommd call rfcomm_sk_state_change() on that child (taking lock_sock(child) under rfcomm_mutex, and dereferencing bt_sk(child)->parent). Bluetooth requires radio range, so the vector is Adjacent.\nAC:H - The peer can send SABM and DISC at will, but both the ABBA deadlock and the late-enqueue window need the victim to close its listener at that moment. That window runs from rfcomm_sock_shutdown dropping the listener lock to cleanup_listen setting BT_CLOSED, and the peer cannot control when the application closes the socket.\nPR:N - rfcomm_connect_ind() only checks for a BT_LISTEN socket on the channel and for room in the backlog before it enqueues a child, so the peer needs no credentials.\nUI:N - No victim action beyond normal operation is needed. A service closing its RFCOMM listener on its own (exit, restart, or Bluetooth teardown) is a timing condition and is counted in AC:H.\nS:U - The deadlock and the dangling parent pointer both stay inside kernel RFCOMM socket state and do not cross a virtualization or hardware boundary.\nC:H - A child enqueued after the drain keeps bt_sk(sk)->parent pointing at the listener, but bt_accept_enqueue takes no reference on it, so rfcomm_sock_kill frees the listener while the pointer is still live. A later state change then reads the freed sock through parent->sk_data_ready, a use-after-free that can be groomed for disclosure.\nI:H - On the peer's DISC, rfcomm_sk_state_change calls bt_accept_unlink(), which does list_del on the freed listener's accept_q and decrements its backlog, then makes an indirect call through the freed parent->sk_data_ready. That is a write to freed memory and a call through a function pointer an attacker can replace.\nA:H - The ABBA blocks krfcommd forever while it holds rfcomm_mutex (rfcomm_dlc_close in the closer against lock_sock(child) in rfcomm_sk_state_change). That stops all RFCOMM processing and hangs the closing task, and the use-after-free path can oops the kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bluetooth/rfcomm/sock.c" ], "versions": [ { "version": "b7ce436a5d798bc59e71797952566608a4b4626b", "lessThan": "eb4adaa46e4c9e6efa7be3ce06398f4d7c39b57c", "status": "affected", "versionType": "git" }, { "version": "b7ce436a5d798bc59e71797952566608a4b4626b", "lessThan": "4aafb47301a799d3e01230d6568c4e93524e1523", "status": "affected", "versionType": "git" }, { "version": "b7ce436a5d798bc59e71797952566608a4b4626b", "lessThan": "c741977e413f5b49d306700820fb55ccb8269f5a", "status": "affected", "versionType": "git" }, { "version": "b7ce436a5d798bc59e71797952566608a4b4626b", "lessThan": "c6792c441767256030606eb82dca5d5fc360dd9a", "status": "affected", "versionType": "git" }, { "version": "b7ce436a5d798bc59e71797952566608a4b4626b", "lessThan": "bfce253f039eb5f58b810af267942a9f59207254", "status": "affected", "versionType": "git" }, { "version": "b7ce436a5d798bc59e71797952566608a4b4626b", "lessThan": "18174b166547ef41973cc19feb5ef9cab39a8def", "status": "affected", "versionType": "git" }, { "version": "b7ce436a5d798bc59e71797952566608a4b4626b", "lessThan": "801fb950cae7048eb7d83b18857d1ca37b8cd5a4", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bluetooth/rfcomm/sock.c" ], "versions": [ { "version": "5.15", "status": "affected" }, { "version": "0", "lessThan": "5.15", "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": "6.18.54", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.8", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "5.15.222" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.1.189" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.6.158" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.18.54" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.2.8" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/eb4adaa46e4c9e6efa7be3ce06398f4d7c39b57c" }, { "url": "https://git.kernel.org/stable/c/4aafb47301a799d3e01230d6568c4e93524e1523" }, { "url": "https://git.kernel.org/stable/c/c741977e413f5b49d306700820fb55ccb8269f5a" }, { "url": "https://git.kernel.org/stable/c/c6792c441767256030606eb82dca5d5fc360dd9a" }, { "url": "https://git.kernel.org/stable/c/bfce253f039eb5f58b810af267942a9f59207254" }, { "url": "https://git.kernel.org/stable/c/18174b166547ef41973cc19feb5ef9cab39a8def" }, { "url": "https://git.kernel.org/stable/c/801fb950cae7048eb7d83b18857d1ca37b8cd5a4" } ], "title": "Bluetooth: RFCOMM: avoid socket lock inversion in listener cleanup", "x_generator": { "engine": "bippy-1.2.0" } } } }