SB20260912237 - Race condition in Linux kernel sunrpc

Description

This security bulletin contains information about 1 vulnerability.

1) Race condition (CVE-ID: CVE-2026-89540)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: 2 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

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.

Remediation

Install update from vendor's website.

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