Deadlock in Linux kernel - CVE-2026-64206

Vulnerability identifier: #VU138911

CSH Severity: Medium

CVSS v4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-64206

CWE-ID: CWE-833

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper locking in the Bluetooth L2CAP connection teardown path when canceling pending receive work during connection deletion. A remote attacker can trigger Bluetooth L2CAP traffic and connection teardown to cause a denial of service.

The issue can deadlock between the pending_rx_work worker and the teardown path in l2cap_conn_del().

Linux kernel
Debian Linux
Ubuntu
linux (Debian package)
linux (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Debian package) - update to 6.12.100-1
linux (Ubuntu package) - addressed in versions 7.0.0-31.31, 7.0.0-31.31.1, 7.0.0-31.31~24.04.1, 7.0.0-1006.7, 7.0.0-1011.11~24.04.1, 7.0.0-1012.12, 7.0.0-1012.12~24.04.1
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1013.13

• https://git.kernel.org/stable/c/2641a9e0a1dd4af2e21995470a21d55dd35e5203
• https://git.kernel.org/stable/c/d5616beb3355b5fca2280d796c1cf7ada4ee6551
• https://git.kernel.org/stable/c/e96fbac8d3a73b0bc165383c092a30628561d320

• Deadlock in Linux kernel bluetooth
• Debian update for linux
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux
• Ubuntu update for linux-gcp-7.0