CVE-2026-64206

Published Jul 20, 2026

Last updated 2 days ago

CVSS high 8.8

Overview

Description
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.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Secondary
Base score
8.8
Impact score
5.9
Exploitability score
2.8
Vector string
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
NVD-CWE-Other
134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-362

Social media

Hype score
Not currently trending

  1. 🚨 Linux kernel patched 400+ vulnerabilities in ~24 hours (July 19-20). Key CVEs to know: 🔹 CVE-2026-64187 – XFS recovery failure 🔹 CVE-2026-64206 – Bluetooth L2CAP locking issue 🔹 CVE-2026-64192 – BPF inode-storage map flaw 🔹 CVE-2026-64188 – UAF in Qual

    @techepages

    21 Jul 2026

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  2. 🚨 New Linux kernel CVEs disclosed (July 19-20): deadlocks, livelocks & NULL pointer crashes across XFS, Bluetooth L2CAP, netfilter, and networking subsystems. Standouts: 🔹 CVE-2026-64206: Bluetooth teardown deadlock 🔹 CVE-2026-64187: XFS log recovery corruption

    @techepages

    21 Jul 2026

    62 Impressions

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Configurations

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References

Sources include official advisories and independent security research.