CVE-2026-23063 uacce: ensure safe queue release with state management
A null pointer dereference in the Linux kernel uacce driver can cause a system crash during concurrent queue release and device removal.
- 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-2026-23063?
CVE-2026-23063 is a medium-severity vulnerability in Linux kernel, published on 4 Feb 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:
uacce: ensure safe queue release with state management
Directly calling `put_queue` carries risks since it cannot guarantee that resources of `uacce_queue` have been fully released beforehand. So adding a `stop_queue` operation for the UACCE_CMD_PUT_Q command and leaving the `put_queue` operation to the final resource release ensures safety.
Queue states are defined as follows: - UACCE_Q_ZOMBIE: Initial state - UACCE_Q_INIT: After opening `uacce` - UACCE_Q_STARTED: After `start` is issued via `ioctl`
When executing `poweroff -f` in virt while accelerator are still working, `uacce_fops_release` and `uacce_remove` may execute concurrently. This can cause `uacce_put_queue` within `uacce_fops_release` to access a NULL `ops` pointer. Therefore, add state checks to prevent accessing freed pointers.
Weakness: CWE-476
Which versions are affected by CVE-2026-23063?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-23063?
Apply the vendor's patch.
Is CVE-2026-23063 being exploited?
There is no known exploitation of CVE-2026-23063 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-23063, DEBIAN-CVE-2026-23063, GHSA-q353-prfj-6jcp, ROOT-OS-UBUNTU-2204-CVE-2026-23063, ROOT-OS-UBUNTU-2404-CVE-2026-23063, UBUNTU-CVE-2026-23063.