Executive brief
A vulnerability was identified in the Linux kernel's Intel QuickAssist Technology (QAT) driver, which provides hardware acceleration for cryptography and compression. The driver contained an unnecessary control interface that increased the system's attack surface and was the subject of multiple bug reports. To resolve this, developers have removed the unused interface to prevent potential exploitation and improve system stability.
Technical details
The Intel QAT driver (crypto: qat) exposed a character device (qat_adf_ctl) with IOCTLs for device configuration and lifecycle management (start, stop, status). These IOCTLs were not part of any public uAPI header and had no known users, as device lifecycle is managed via sysfs. The interface was identified as a source of multiple vulnerabilities and an unnecessary increase in the kernel's attack surface. The fix involves the complete removal of the character device, IOCTL definitions, and related data structures (adf_dev_status_info, adf_user_cfg_ctl_data, etc.) to eliminate the vulnerable code paths.
Affected products
- Linux Linux Kernel d8cba25d2c68
Timeline
- 2026-07-25: disclosed: CVE published
- 2026-07-04: patched: Patch committed to stable tree
References
- https://git.kernel.org/stable/c/071590a44cbc38483fceb1ab943363ec26868e1b
- https://git.kernel.org/stable/c/1de076f43e64bf65fbe7280a269c70e0e60518df
- https://git.kernel.org/stable/c/3ae49dd04dbb11fb73f17f58a982dba128abe83a
- https://git.kernel.org/stable/c/6848a6e39cac44fdb7cb88f0f777df62172d1551
- https://git.kernel.org/stable/c/a4999664a5ef77bdb0c6e6b935f581ac8ce6b63a
- https://git.kernel.org/stable/c/b1ea97076bd0a5196290deba172034e480646727
- https://git.kernel.org/stable/c/b8ebf008696de1ec08c90d51f94d7e40bd448be1