Use-after-free in Linux kernel - CVE-2026-89928
Published: September 17, 2026
Vulnerability identifier: #VU150351
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-2026-89928
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 KVM x86 MMU lockless rmap walk when performing lockless rmap aging while a writer populates or frees an rmap. A local user can trigger lockless rmap aging concurrently with rmap modification to compromise confidentiality, integrity, and availability.
The issue requires CONFIG_KVM_MMU_LOCKLESS_AGING to be enabled.
Affected software
Linux kernel
How to mitigate CVE-2026-89928
Install security update from vendor's repository.