Race condition in Linux kernel - CVE-2026-89540

Vulnerability details

The vulnerability allows a local user to cause a resource leak.

The vulnerability exists due to an initialization race condition in the use-gss-proxy proc entry initialization when writing to the newly published proc entry before gssp_lock is initialized. A local user can win the initialization race and write to the proc entry to cause a resource leak.

The race window can widen when the auth_rpcgss module is loaded for live network namespaces.

Affected software

How to mitigate CVE-2026-89540

External References

• https://git.kernel.org/stable/c/3f019571928b269feebcff59926ec13294215e0e
• https://git.kernel.org/stable/c/5ce1ed6159731a41fdd0b03eedbed4e147036a5a
• https://git.kernel.org/stable/c/edeefb111d6181a4aa278f415b005efe284b9489
• https://git.kernel.org/stable/c/f15b87521168c2a92cb1931f532cba422f856f01

Related Security Bulletins

• Race condition in Linux kernel sunrpc