CVE-2026-80721 Bluetooth: ISO: ensure no dangling hcon references in iso_conn
A use-after-free vulnerability in the Linux kernel Bluetooth ISO subsystem allows attackers to cause denial of service or execute arbitrary code.
- 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-2026-80721?
CVE-2026-80721 is a high-severity use after free vulnerability in Linux, published on 28 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: ISO: ensure no dangling hcon references in iso_conn
After iso_conn_del(), ISO sockets should not dereference the hcon any more. Currently, clearing iso_conn::hcon relies on iso_conn_del() releasing the last reference to the iso_conn.
Simplify this by explicitly clearing conn->hcon in iso_conn_del(), to avoid more complex reasoning on races about who holds the last reference.
Which versions are affected by CVE-2026-80721?
How do I fix CVE-2026-80721?
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-2026-80721 being exploited?
There is no known exploitation of CVE-2026-80721 in the wild and no public exploit code.
Sources
Also known as AZL-98142, BELL-CVE-2026-80721, DEBIAN-CVE-2026-80721, GHSA-28qm-9qmh-h457, UBUNTU-CVE-2026-80721.