SB2026052205 - Use-after-free in Linux kernel locking
Published: May 22, 2026
Security Bulletin ID
SB2026052205
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-43499)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 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
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to use-after-free in remove_waiter() when rolling back a proxy lock from futex_requeue(). A local user can trigger the affected rtmutex slowlock and proxy-lock rollback path to cause a denial of service.
The issue can leave waiter task state uncleared and operate on the wrong top priority waiter task.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/3bfdc63936dd4773109b7b8c280c0f3b5ae7d349
- https://git.kernel.org/stable/c/3fb7394a837740770f0d6b4b30567e60786a63f2
- https://git.kernel.org/stable/c/6d52dfcb2a5db86e346cf51f8fcf2071b8085166
- https://git.kernel.org/stable/c/88614876370aac8ad1050ad785a4c095ba17ac11
- https://git.kernel.org/stable/c/8a1fc8d698ac5e5916e3082a0f74450d71f9611f