CVE-2026-64406 (CVSS 8)

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.

Is your site exposed to CVE-2026-64406?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

8.0

HIGH

CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0027

Probability of exploitation

0.20%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/0a98ff4e7b867f72fbb4e1237d81e9fa02ded0a0 https://git.kernel.org/stable/c/26168db1ce5a9766cde021b18e590a101c056614 https://git.kernel.org/stable/c/4bd0b274054f2679f28b70222b607bb0afc3ab9a https://git.kernel.org/stable/c/50c662bdcd51b03033a0abed6716bfd377ba1049 https://git.kernel.org/stable/c/6303ed4bbe0095f4cc195225479bf506e010d1db https://git.kernel.org/stable/c/96ad400d5132eb333f28f6f1e2d58f0728ca9547 https://git.kernel.org/stable/c/c0577c55219be42b6ea2ea8db11e85bfab6f4e8d https://git.kernel.org/stable/c/c66a95e60b65d876a927123b0ed36bd6177d9ca6

Frequently Asked Questions

What is CVE-2026-64406? +

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. It has a CVSS v3.1 base score of 8.0 (HIGH).

How severe is CVE-2026-64406? +

CVE-2026-64406 has a CVSS v3.1 score of 8.0 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0027, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-64406? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

CVE-2026-64406