{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-99239", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.403Z", "datePublished": "2026-11-02T16:06:43.262Z", "dateUpdated": "2026-11-02T16:06:43.262Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-11-02T16:06:43.262Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: refuse __l2cap_chan_add if chan already has conn\n\nl2cap_chan may be linked to l2cap_conn at most once. This is assumed in\nseveral places, eg l2cap_chan_del cleanup.\n\nThere is a TOCTOU race where the invariant is violated:\n\n [Task 1] [Task 2]\n l2cap_chan_connect l2cap_sock_bind\n l2cap_chan_lock lock_sock\n l2cap_state_change if (sk->sk_state != BT_OPEN)\n chan->state = BT_CONNECT\n l2cap_sock_state_change_cb chan->state = BT_BOUND\n sk->sk_state = BT_BOUND\n lock_sock <------------------ release_sock\n sk->sk_state = BT_CONNECT\n\nl2cap_sock_connect() does not check sk->sk_state, so since chan->state\nis now BT_BOUND, subsequent connect() ends up with second\n__l2cap_chan_add.\n\nExplicitly document and check the invariant in __l2cap_chan_add with\nWARN_ON_ONCE. The only callsite where it could be hit is\nl2cap_chan_connect, so add pre-check there to avoid relying on\nchan->state. chan->state read/write is not properly guarded currently so\nthere can be other TOCTOUC problems.\n\nAdd l2cap_lock_chan in l2cap_sock_bind() to guard chan->state write."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The double add is a local TOCTOU: l2cap_sock_connect()\u2192l2cap_chan_connect()\u2192__l2cap_chan_add() races l2cap_sock_bind(), which overwrites chan->state to BT_BOUND so a later connect() links the same l2cap_chan again. No received L2CAP/HCI PDU carries that state; a radio peer cannot issue those syscalls.\nAC:L - The attacker owns both threads. bind() holds lock_sock while l2cap_state_change() blocks in l2cap_sock_state_change_cb(); bind() then sets chan->state=BT_BOUND. l2cap_sock_connect() never checks sk->sk_state, so a later connect() observes BT_BOUND and calls __l2cap_chan_add() again. The race is attacker-driven and retryable.\nPR:L - l2cap_sock_create() requires capable(CAP_NET_RAW) only for SOCK_RAW; SOCK_SEQPACKET/STREAM used here have no capability gate. l2cap_add_psm() auto-picks a dynamic PSM (BR/EDR >=0x1001) without CAP_NET_BIND_SERVICE. bt_sock_create() is init_net-only, so this is an ordinary unprivileged local user.\nUI:N - The attacker opens their own AF_BLUETOOTH/BTPROTO_L2CAP socket and issues bind()/connect(). hci_connect_acl() creates the hci_conn, l2cap_conn_add() publishes l2cap_data, and __l2cap_chan_add() runs before any remote Connection Complete or pairing prompt.\nS:U - __l2cap_chan_add() corrupts the host kernel l2cap_chan.list linked into l2cap_conn.chan_l, which l2cap_chan_del() and l2cap_conn_del() then walk; the impact stays in the kernel L2CAP/HCI authority and does not cross a VM, IOMMU, or sandbox boundary.\nC:H - A second __l2cap_chan_add() to another l2cap_conn list_add_tail()s the same chan->list without unlinking it from the first conn->chan_l. l2cap_conn_del()'s list_for_each_entry_safe then follows those stale pointers and treats the other conn's list head as an l2cap_chan, an adjacent-slab type confusion that can be sprayed for a kernel read.\nI:H - l2cap_chan_del() list_del()s the twice-inserted chan->list, writing next/prev of the other connection's nodes, and l2cap_conn_del() calls chan->ops->teardown/close on the type-confused object. That unlink write plus ops-pointer invocation is a write/control-flow primitive.\nA:H - Inserting chan->list into the same conn->chan_l twice makes a self-loop, so __l2cap_get_chan_by_scid(), l2cap_conn_start(), and l2cap_conn_del() hang in list_for_each_entry; after list_del() the leftover head still points at the poisoned node and oopses."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/bluetooth/l2cap_core.c", "net/bluetooth/l2cap_sock.c"], "versions": [{"version": "8f90405a4a6f1f1880dc07996b47bf57c712bd8a", "lessThan": "85cc289eb08afa975375f838187369e68b429ee0", "status": "affected", "versionType": "git"}, {"version": "32d783cafb46ff3ca58e6f9fd62c9c5f35eaf26b", "lessThan": "820579652b24ce277e0097cd65b42bd9b7b8bf07", "status": "affected", "versionType": "git"}, {"version": "8922c7940bae9ce4b1736dddb6362370793835c2", "lessThan": "e618d928ec7f88cbeadfa3542adcac40f474e629", "status": "affected", "versionType": "git"}, {"version": "91047a4396a8b1857a6f712a90cf33ec0012b189", "lessThan": "fabaff1c59ff2cc89cb7e5bd0186a5e15f0c73b2", "status": "affected", "versionType": "git"}, {"version": "0b0e2bf39cf99e458d991b9df253727e036a7d7d", "lessThan": "52fe88e4ef87311eee32b45c65603e7c69e75e7d", "status": "affected", "versionType": "git"}, {"version": "d3b739db5dc6f688a60d56da872fabaf65246032", "lessThan": "10c705dd706aa93164ba41f2566f15206d6c178e", "status": "affected", "versionType": "git"}, {"version": "b66774b48dd98f07254951f74ea6f513efe7ff8b", "lessThan": "73820561d8cbfd3364a29b8fa77f1707f26029da", "status": "affected", "versionType": "git"}, {"version": "b66774b48dd98f07254951f74ea6f513efe7ff8b", "lessThan": "d3afd7803f9bc2a8c4270199497b60158b2fc647", "status": "affected", "versionType": "git"}, {"version": "50c38d9f42a529691e4e67ea9cedf4f0bfc8d277", "status": "affected", "versionType": "git"}, {"version": "5.10.265", "lessThan": "5.10.273", "status": "affected", "versionType": "semver"}, {"version": "5.15.216", "lessThan": "5.15.224", "status": "affected", "versionType": "semver"}, {"version": "6.1.183", "lessThan": "6.1.191", "status": "affected", "versionType": "semver"}, {"version": "6.6.145", "lessThan": "6.6.161", "status": "affected", "versionType": "semver"}, {"version": "6.12.97", "lessThan": "6.12.115", "status": "affected", "versionType": "semver"}, {"version": "6.18.39", "lessThan": "6.18.60", "status": "affected", "versionType": "semver"}, {"version": "7.1.4", "lessThan": "7.2", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/bluetooth/l2cap_core.c", "net/bluetooth/l2cap_sock.c"], "versions": [{"version": "7.2", "status": "affected"}, {"version": "0", "lessThan": "7.2", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.273", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.224", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.191", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.161", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.115", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.60", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.14", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3.1", "lessThanOrEqual": "7.3.*", "status": "unaffected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10.265", "versionEndExcluding": "5.10.273"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15.216", "versionEndExcluding": "5.15.224"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.183", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.145", "versionEndExcluding": "6.6.161"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12.97", "versionEndExcluding": "6.12.115"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18.39", "versionEndExcluding": "6.18.60"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.2", "versionEndExcluding": "7.2.14"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.2", "versionEndExcluding": "7.3.1"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.1.4"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/85cc289eb08afa975375f838187369e68b429ee0"}, {"url": "https://git.kernel.org/stable/c/820579652b24ce277e0097cd65b42bd9b7b8bf07"}, {"url": "https://git.kernel.org/stable/c/e618d928ec7f88cbeadfa3542adcac40f474e629"}, {"url": "https://git.kernel.org/stable/c/fabaff1c59ff2cc89cb7e5bd0186a5e15f0c73b2"}, {"url": "https://git.kernel.org/stable/c/52fe88e4ef87311eee32b45c65603e7c69e75e7d"}, {"url": "https://git.kernel.org/stable/c/10c705dd706aa93164ba41f2566f15206d6c178e"}, {"url": "https://git.kernel.org/stable/c/73820561d8cbfd3364a29b8fa77f1707f26029da"}, {"url": "https://git.kernel.org/stable/c/d3afd7803f9bc2a8c4270199497b60158b2fc647"}], "title": "Bluetooth: L2CAP: refuse __l2cap_chan_add if chan already has conn", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/bluetooth/l2cap_core.c", "net/bluetooth/l2cap_sock.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "85cc289eb08afa975375f838187369e68b429ee0", "status": "affected", "version": "8f90405a4a6f1f1880dc07996b47bf57c712bd8a", "versionType": "git"}, {"lessThan": "820579652b24ce277e0097cd65b42bd9b7b8bf07", "status": "affected", "version": "32d783cafb46ff3ca58e6f9fd62c9c5f35eaf26b", "versionType": "git"}, {"lessThan": "e618d928ec7f88cbeadfa3542adcac40f474e629", "status": "affected", "version": "8922c7940bae9ce4b1736dddb6362370793835c2", "versionType": "git"}, {"lessThan": "fabaff1c59ff2cc89cb7e5bd0186a5e15f0c73b2", "status": "affected", "version": "91047a4396a8b1857a6f712a90cf33ec0012b189", "versionType": "git"}, {"lessThan": "52fe88e4ef87311eee32b45c65603e7c69e75e7d", "status": "affected", "version": "0b0e2bf39cf99e458d991b9df253727e036a7d7d", "versionType": "git"}, {"lessThan": "10c705dd706aa93164ba41f2566f15206d6c178e", "status": "affected", "version": "d3b739db5dc6f688a60d56da872fabaf65246032", "versionType": "git"}, {"lessThan": "73820561d8cbfd3364a29b8fa77f1707f26029da", "status": "affected", "version": "b66774b48dd98f07254951f74ea6f513efe7ff8b", "versionType": "git"}, {"lessThan": "d3afd7803f9bc2a8c4270199497b60158b2fc647", "status": "affected", "version": "b66774b48dd98f07254951f74ea6f513efe7ff8b", "versionType": "git"}, {"status": "affected", "version": "50c38d9f42a529691e4e67ea9cedf4f0bfc8d277", "versionType": "git"}, {"lessThan": "5.10.273", "status": "affected", "version": "5.10.265", "versionType": "semver"}, {"lessThan": "5.15.224", "status": "affected", "version": "5.15.216", "versionType": "semver"}, {"lessThan": "6.1.191", "status": "affected", "version": "6.1.183", "versionType": "semver"}, {"lessThan": "6.6.161", "status": "affected", "version": "6.6.145", "versionType": "semver"}, {"lessThan": "6.12.115", "status": "affected", "version": "6.12.97", "versionType": "semver"}, {"lessThan": "6.18.60", "status": "affected", "version": "6.18.39", "versionType": "semver"}, {"lessThan": "7.2", "status": "affected", "version": "7.1.4", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/bluetooth/l2cap_core.c", "net/bluetooth/l2cap_sock.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "7.2"}, {"lessThan": "7.2", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.273", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.224", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.161", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.115", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.60", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.14", "versionType": "semver"}, {"lessThanOrEqual": "7.3.*", "status": "unaffected", "version": "7.3.1", "versionType": "semver"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: refuse __l2cap_chan_add if chan already has conn\n\nl2cap_chan may be linked to l2cap_conn at most once. This is assumed in\nseveral places, eg l2cap_chan_del cleanup.\n\nThere is a TOCTOU race where the invariant is violated:\n\n [Task 1] [Task 2]\n l2cap_chan_connect l2cap_sock_bind\n l2cap_chan_lock lock_sock\n l2cap_state_change if (sk->sk_state != BT_OPEN)\n chan->state = BT_CONNECT\n l2cap_sock_state_change_cb chan->state = BT_BOUND\n sk->sk_state = BT_BOUND\n lock_sock <------------------ release_sock\n sk->sk_state = BT_CONNECT\n\nl2cap_sock_connect() does not check sk->sk_state, so since chan->state\nis now BT_BOUND, subsequent connect() ends up with second\n__l2cap_chan_add.\n\nExplicitly document and check the invariant in __l2cap_chan_add with\nWARN_ON_ONCE. The only callsite where it could be hit is\nl2cap_chan_connect, so add pre-check there to avoid relying on\nchan->state. chan->state read/write is not properly guarded currently so\nthere can be other TOCTOUC problems.\n\nAdd l2cap_lock_chan in l2cap_sock_bind() to guard chan->state write."}], "id": "CVE-2026-99239", "lastModified": "2026-11-02T16:17:49.540", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-11-02T16:17:49.540", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/10c705dd706aa93164ba41f2566f15206d6c178e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/52fe88e4ef87311eee32b45c65603e7c69e75e7d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/73820561d8cbfd3364a29b8fa77f1707f26029da"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/820579652b24ce277e0097cd65b42bd9b7b8bf07"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/85cc289eb08afa975375f838187369e68b429ee0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d3afd7803f9bc2a8c4270199497b60158b2fc647"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e618d928ec7f88cbeadfa3542adcac40f474e629"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/fabaff1c59ff2cc89cb7e5bd0186a5e15f0c73b2"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{}