CVE-2026-74528 Bluetooth: hci_sync: hold conn in hci_past_sync() callback
A use-after-free vulnerability in the Linux kernel Bluetooth subsystem allows attackers to execute arbitrary code or escalate privileges via crafted HCI packets.
- 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-2026-74528?
CVE-2026-74528 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_sync: hold conn in hci_past_sync() callback
Avoids giving freed pointers to hci_conn_valid(), which kmalloc may have reused.
Hold refcount to avoid that.
Which versions are affected by CVE-2026-74528?
How do I fix CVE-2026-74528?
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-2026-74528 being exploited?
There is no known exploitation of CVE-2026-74528 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-74528, GHSA-cjhj-vjxx-32hg, UBUNTU-CVE-2026-74528.