CVE-2026-74302 Bluetooth: hci_core: Fix UAF in hci_unregister_dev()
A use-after-free in the Linux kernel Bluetooth subsystem allows attackers to execute arbitrary code or escalate privileges during device teardown.
- 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-2026-74302?
CVE-2026-74302 is a high-severity use after free vulnerability in Linux, published on 15 Aug 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: hci_core: Fix UAF in hci_unregister_dev()
hci_unregister_dev() does not disable cmd_timer and ncmd_timer before the hci_dev structure is freed. If a timeout fires during device teardown, the callback dereferences freed memory (including the hdev->reset function pointer), leading to a use-after-free.
Add disable_delayed_work_sync() calls alongside the existing disable_work_sync() calls to ensure both timers are fully quiesced before teardown proceeds.
Which versions are affected by CVE-2026-74302?
How do I fix CVE-2026-74302?
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-2026-74302 being exploited?
There is no known exploitation of CVE-2026-74302 in the wild and no public exploit code.
Sources
Also known as AZL-96477, BELL-CVE-2026-74302, DEBIAN-CVE-2026-74302, GHSA-78xg-w78v-wc27, UBUNTU-CVE-2026-74302.