Improper locking in Linux kernel - CVE-2026-74486

Vulnerability identifier: #VU143295

CSH Severity: Low

CVSS v4: 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]

CVE-ID: CVE-2026-74486

CWE-ID: CWE-667

Exploitation vector: Local access

Exploit availability: No public exploit available

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.

Linux kernel
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17

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

• Improper locking in Linux kernel fs
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more