CVE-2026-64406 Bluetooth: fix UAF in bt_accept_dequeue()
A use-after-free in the Linux kernel Bluetooth subsystem allows attackers to execute arbitrary code or escalate privileges via crafted L2CAP socket operations.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-64406?
CVE-2026-64406 is a high-severity use after free vulnerability in Linux kernel, published on 25 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: fix UAF in bt_accept_dequeue()
bt_accept_get() takes a temporary reference before dropping the accept queue lock. bt_accept_dequeue() currently drops that reference before bt_accept_unlink(), leaving only the queue reference.
bt_accept_unlink() drops the queue reference. The subsequent sock_hold() therefore accesses freed memory if it was the final reference, as observed by KASAN during listening L2CAP socket cleanup.
Retain the temporary queue-walk reference through unlink and hand it to the caller on success. Drop it explicitly on the closed and not-yet-connected paths.
Weakness: CWE-416
Which versions are affected by CVE-2026-64406?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-64406?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-64406 being exploited?
There is no known exploitation of CVE-2026-64406 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-93536, BELL-CVE-2026-64406, DEBIAN-CVE-2026-64406, GHSA-vm2j-8ch2-x289, ROOT-OS-DEBIAN-12-CVE-2026-64406, ROOT-OS-UBUNTU-2204-CVE-2026-64406 and 1 more.