Use-after-free in Linux kernel - CVE-2026-89960
Published: September 17, 2026
Vulnerability identifier: #VU150326
CSH Severity: Low
CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-89960
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to compromise confidentiality, integrity, and availability.
The vulnerability exists due to a use-after-free in the s390 VFIO AP mediated-device KVM assignment handling when executing a PQAP instruction in a guest after a failed conflicting mediated-device assignment and subsequent freeing of the mediated device. A local user can trigger a conflicting mediated-device assignment and execute a PQAP instruction in the guest to compromise confidentiality, integrity, and availability.
Affected software
Linux kernel
How to mitigate CVE-2026-89960
Install security update from vendor's repository.
External References
- https://git.kernel.org/stable/c/13bfc94eef389bd664ffc67b00184919902c938a
- https://git.kernel.org/stable/c/4400270ec0348d05dc0439d8f0130853ce7f9e20
- https://git.kernel.org/stable/c/6a180adafc2a8a5fbe815985c71b2201e93ab5e1
- https://git.kernel.org/stable/c/eb6cc898501a004c0fa8aab951351d9c959b91cc
- https://git.kernel.org/stable/c/fc069d00a0dbef40042fd681554d48dcd5a1d524