CVE-2026-63822 wifi: ath11k: fix warning when unbinding
A double-free vulnerability in the ath11k Wi-Fi driver can cause a kernel warning and potential denial of service when unbinding the device after a firmware initialization error.
- 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-2026-63822?
CVE-2026-63822 is an use after free vulnerability in Linux, published on 19 Jul 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:
wifi: ath11k: fix warning when unbinding
If there is an error during some initialization related to firmware, the buffers dp->tx_ring[i].tx_status are released. However this is released again when the device is unbinded (ath11k_pci), and we get: WARNING: CPU: 0 PID: 6231 at mm/slub.c:4368 free_large_kmalloc+0x57/0x90 Call Trace: free_large_kmalloc ath11k_dp_free ath11k_core_deinit ath11k_pci_remove ...
The issue is always reproducible from a VM because the MSI addressing initialization is failing.
In order to fix the issue, just set the buffers to NULL after releasing in order to avoid the double free.
Which versions are affected by CVE-2026-63822?
How do I fix CVE-2026-63822?
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-2026-63822 being exploited?
There is no known exploitation of CVE-2026-63822 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-63822, DEBIAN-CVE-2026-63822, GHSA-783h-g799-4r2q, ROOT-OS-DEBIAN-11-CVE-2026-63822, ROOT-OS-UBUNTU-2204-CVE-2026-63822, UBUNTU-CVE-2026-63822.