Use After Free in Linux
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.
Vulnerability class: Use-After-Free
EPSS: 0.003 (19.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.0 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux — versions 5.15.210, 7eebd4c2c86f573af87ff165d08a83432eb0b919, 7.2
- Linux Linux_kernel — versions 7.1, 7.2
Weakness classification (CWE)
References
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
Frequently asked questions
- What is CVE-2026-64406?
- CVE-2026-64406 is a high-severity vulnerability in Linux, classified under Use After Free. CVSS score: 8.0/10. Published 2026-07-25.
- How severe is CVE-2026-64406?
- High severity. CVSS v3 base score is 8.0 out of 10.