Improper Initialization in Linux kernel - CVE-2026-64476
Published: July 27, 2026
Vulnerability identifier: #VU139454
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-64476
CWE-ID: CWE-665
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper state management in vfio-pci runtime power management handling when changing the disable_idle_d3 setting for devices already bound to vfio-pci variant drivers. A local user can change the sysfs module parameter and trigger unbalanced power management operations to cause a denial of service.
The issue occurs because the setting was latched globally at module initialization rather than consistently per device, creating a window where existing bound devices could operate with inconsistent power management behavior.
Affected software
Linux kernel
How to mitigate CVE-2026-64476
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
External References
- https://git.kernel.org/stable/c/062b820290bcb9778e43a73597df76e9bb08acfb
- https://git.kernel.org/stable/c/332d785f9ae426eeeb92527872adf09d84101ba3
- https://git.kernel.org/stable/c/4575e9aac5336d1365138c0284773bf8da4b1fa3
- https://git.kernel.org/stable/c/654710ef3135c4546b20a903bc23a51b0c44d6c8
- https://git.kernel.org/stable/c/b98296816d31441b307ef9fa8670dcf5a55e5505
- https://git.kernel.org/stable/c/f6c67cf0051f96ba61d186731d3d9409b9927db2