CVE-2026-74661 mac802154: fix netdev use-after-free in beacon worker
A use-after-free vulnerability in the Linux kernel's mac802154 beacon worker allows attackers to cause denial of service or execute arbitrary code.
- 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-2026-74661?
CVE-2026-74661 is a high-severity use after free vulnerability in Linux, published on 22 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:
mac802154: fix netdev use-after-free in beacon worker
mac802154_beacon_worker() reads local->beacon_req under RCU and derives the sub-interface from the request, but then drops the RCU read lock and continues to use both sdata and the embedded wpan_dev.
mac802154_stop_beacons_locked() cancels only pending beacon work, clears local->beacon_req and frees the request. A beacon worker that is already running can therefore continue after interface teardown and dereference the freed netdev private area.
The scan worker already pins the netdev before leaving RCU. Apply the same lifetime rule to the beacon worker: take a netdev reference while the request is still protected by RCU, and release it on all paths that continue after the reference is acquired.
Which versions are affected by CVE-2026-74661?
How do I fix CVE-2026-74661?
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-2026-74661 being exploited?
There is no known exploitation of CVE-2026-74661 in the wild and no public exploit code.
Sources
Also known as AZL-97263, BELL-CVE-2026-74661, DEBIAN-CVE-2026-74661, GHSA-6r5m-rv77-x5qr, UBUNTU-CVE-2026-74661.