CVE-2026-64529 crypto: qat - remove unused character device and IOCTLs
Removal of unused QAT driver IOCTLs reduces the kernel attack surface by eliminating an unneeded character device interface.
- 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-2026-64529?
CVE-2026-64529 is a high-severity vulnerability in Linux, published on 25 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:
crypto: qat - remove unused character device and IOCTLs
The QAT driver exposes a character device (qat_adf_ctl) with IOCTLs for device configuration, start, stop, status query and enumeration. These IOCTLs are not part of any public uAPI header and have no known in-tree or out-of-tree users. Device lifecycle is already managed via sysfs.
The ioctl interface also increases the attack surface and is the subject of a number of bug reports.
Remove the character device, the IOCTL definitions, and the related data structures (adf_dev_status_info, adf_user_cfg_key_val, adf_user_cfg_section, adf_user_cfg_ctl_data). Drop the now-unused adf_cfg_user.h header and strip adf_ctl_drv.c down to the minimal module_init/module_exit hooks for workqueue, AER, and crypto/compression algorithm registration.
Clean up leftover dead code that was only reachable from the removed IOCTL paths: adf_cfg_del_all(), adf_devmgr_verify_id(), adf_devmgr_get_num_dev(), adf_devmgr_get_dev_by_id(), adf_get_vf_real_id() and the unused ADF_CFG macros.
Additionally, drop the entry associated to QAT IOCTLs in ioctl-number.rst.
Weakness: CWE-489
Which versions are affected by CVE-2026-64529?
How do I fix CVE-2026-64529?
Apply the vendor's patch.
Is CVE-2026-64529 being exploited?
There is no known exploitation of CVE-2026-64529 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-64529, DEBIAN-CVE-2026-64529, GHSA-9fhf-pqwj-mfrc, ROOT-OS-UBUNTU-2204-CVE-2026-64529, UBUNTU-CVE-2026-64529.