CVE-2026-74530 Bluetooth: hci_sync: hold conn in hci_connect_big_sync() callback
A use-after-free vulnerability in the Linux kernel Bluetooth subsystem allows attackers to potentially execute code or escalate privileges.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74530?
CVE-2026-74530 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_connect_big_sync() callback
There is theoretical UAF if the conn is freed while the hci_sync task is running.
Hold refcount to avoid that. Handle NULL hcon, return 0 + do nothing to match the previous behavior.
Which versions are affected by CVE-2026-74530?
How do I fix CVE-2026-74530?
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-2026-74530 being exploited?
There is no known exploitation of CVE-2026-74530 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-74530, DEBIAN-CVE-2026-74530, GHSA-65qm-758v-r47w, UBUNTU-CVE-2026-74530.