Use-after-free in Linux kernel - CVE-2026-90121
Published: September 19, 2026
Vulnerability identifier: #VU151360
CSH Severity: Low
CVSS v4: 0 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-90121
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause CPUs to retain associations with freed memory.
The vulnerability exists due to use-after-free in the GICv5 IRS affinity state when IRS initialization fails or an IRS is torn down. A local user can trigger IRS initialization failure or teardown to cause CPUs to retain associations with freed memory.
Affected software
Linux kernel
How to mitigate CVE-2026-90121
Install security update from vendor's repository.