Use-after-free in Linux kernel - CVE-2026-43438
Published: May 8, 2026
Vulnerability identifier: #VU130737
CSH Severity: Low
CVSS v4.0: 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/E:U/U:Clear
CVE-ID: CVE-2026-43438
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in scx_cgroup_init() when handling an error path during cgroup hierarchy iteration. A local user can trigger the vulnerable code path to cause a denial of service.
The issue is caused by an unbalanced css_put() call that can lead to a refcount underflow.
How to mitigate CVE-2026-43438
Install security update from vendor's repository.