CVE-2026-80553 s390/vfio_ccw: Cancel existing workqueues
A use-after-free vulnerability in the s390 vfio_ccw driver allows attackers to execute code or cause a denial of service by triggering workqueue dispatch after memory release.
- 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-2026-80553?
CVE-2026-80553 is a high-severity use after free vulnerability in Linux, published on 26 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:
s390/vfio_ccw: Cancel existing workqueues
The initialization of the io_work and crw_work workqueues begs the question of whether they should be un-initialized. Add the corresponding cleanup tags in _release_dev to ensure work isn't dispatched after the private struct is free'd.
Which versions are affected by CVE-2026-80553?
How do I fix CVE-2026-80553?
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-2026-80553 being exploited?
There is no known exploitation of CVE-2026-80553 in the wild and no public exploit code.
Sources
Also known as AZL-97848, BELL-CVE-2026-80553, DEBIAN-CVE-2026-80553, GHSA-rq35-rvjv-r5cq, UBUNTU-CVE-2026-80553.