SB20260816231 - Improper locking in Linux kernel fs

Description

This security bulletin contains information about 1 vulnerability.

1) Improper locking (CVE-ID: CVE-2026-74486)

CWE-ID: CWE-667 - Improper Locking

CVSSv4: 6.8 [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]

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper handling of write access accounting in load_misc_binary() in fs/binfmt_misc.c when executing a binfmt_misc entry with MISC_FMT_OPEN_FILE and a pre-content watch is added to the registered interpreter after registration. A local user can repeatedly execute the affected entry to cause a denial of service.

The issue can leave the interpreter file unwritable even after the entry and all its users are gone.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/255a758697da87a205e072e0cfc35897b8f743b1
• https://git.kernel.org/stable/c/f0edbaf487e4653a680a7abb91c1df94cb7886aa
• https://git.kernel.org/stable/c/fa5990ca8fd917003e526036bcc50413edb9722c