HighFix available

Bluetooth: L2CAP: cancel pending_rx_work before taking conn->lock

Type: advisorySources: OSV

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: cancel pending_rx_work before taking conn->lock l2cap_conn_del() takes conn->lock and then calls cancel_work_sync() for pending_rx_work. process_pending_rx() takes the same mutex, so teardown can deadlock against the worker it is flushing. This issue was found by our static analysis tool and then manually reviewed against the current tree. The grounded PoC kept the l2cap_conn_ready() -> queue_work(..., &conn->pending_rx_work) submit path, the l2cap_conn_del() -> cancel_work_sync(&conn->pending_rx_work) teardown path, and the process_pending_rx() -> mutex_lock(&conn->lock) worker edge. Lockdep WARNING: possible circular locking dependency detected process_pending_rx+0x21/0x2a [vuln_msv] l2cap_conn_del.constprop.0+0x3f/0x4e [vuln_msv] *** DEADLOCK *** Cancel pending_rx_work before taking conn->lock, matching the existing lock-before-drain ordering used for the two delayed works in the same teardown path. The pending_rx queue is still purged after the work has been cancelled and conn->lock has been acquired.

Products: Kernel
Affected versions: Not specified
Fixed versions: 5.10.261, 5.15.212, 6.1.178, 6.12.97, 6.18.39, 6.6.145, 7.1.4
CVEs: CVE-2026-64206
Confirmed fixed CVEs: Not specified
Updated in this feed: 3 Nov 2026, 17:24 UTC · Revision 1

Source evidence

Bluetooth: L2CAP: cancel pending_rx_work before taking conn->lock

core-osv · Original source

Published 20 Jul 2026, 16:27 UTC

osv:CVE-2026-64206

Kernel

Fixed versions: 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.97, 6.18.39, 7.1.4

Complete source record

{
  "id": "6c036b8817888e5ae33610cad2b0107a5d9cf68567ccbd65a72c30027c8bdaf1",
  "url": "https://osv.dev/vulnerability/CVE-2026-64206",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Bluetooth: L2CAP: cancel pending_rx_work before taking conn->lock",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: cancel pending_rx_work before taking conn->lock l2cap_conn_del() takes conn->lock and then calls cancel_work_sync() for pending_rx_work. process_pending_rx() takes the same mutex, so teardown can deadlock against the worker it is flushing. This issue was found by our static analysis tool and then manually reviewed against the current tree. The grounded PoC kept the l2cap_conn_ready() -> queue_work(..., &conn->pending_rx_work) submit path, the l2cap_conn_del() -> cancel_work_sync(&conn->pending_rx_work) teardown path, and the process_pending_rx() -> mutex_lock(&conn->lock) worker edge. Lockdep WARNING: possible circular locking dependency detected process_pending_rx+0x21/0x2a [vuln_msv] l2cap_conn_del.constprop.0+0x3f/0x4e [vuln_msv] *** DEADLOCK *** Cancel pending_rx_work before taking conn->lock, matching the existing lock-before-drain ordering used for the two delayed works in the same teardown path. The pending_rx queue is still purged after the work has been cancelled and conn->lock has been acquired.",
    "evidence": "osv:CVE-2026-64206",
    "products": [
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        "prerequisites": [],
        "fixed_versions": [
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            "evidence": "/affected/1/ranges"
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          {
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          {
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            "evidence": "/affected/1/ranges"
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        "affected_versions": []
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    "severity": "high",
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      "modified": "2026-10-28T02:30:30.700467628Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/2641a9e0a1dd4af2e21995470a21d55dd35e5203",
        "https://git.kernel.org/stable/c/4a0bb0fd63fe2b0c62e1072cd1811d6f61e0081c",
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        "https://git.kernel.org/stable/c/8de7b386ffad480ca59222b688c94a2da8f0d805",
        "https://git.kernel.org/stable/c/9901f847a762a5d953871dd95767ce2aed3d684d",
        "https://git.kernel.org/stable/c/d5616beb3355b5fca2280d796c1cf7ada4ee6551",
        "https://git.kernel.org/stable/c/e96fbac8d3a73b0bc165383c092a30628561d320",
        "https://git.kernel.org/stable/c/fc0c3b9cf27cfa2a06f66dae1d08c668fe0a2faa",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64206.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-64206",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64206.json"
      }
    },
    "related_cves": [
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    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 497799,
  "published_at": "2026-07-20T16:27:53.885+00:00"
}