Use-after-free in Linux kernel - CVE-2026-46242

 

Use-after-free in Linux kernel - CVE-2026-46242

Published: May 31, 2026


Vulnerability identifier: #VU133094
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-46242
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability: No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel

Detailed vulnerability description

The vulnerability allows a local user to cause memory corruption.

The vulnerability exists due to a use-after-free in ep_remove() in fs/eventpoll.c when removing epoll file references during a race with file release handling. A local user can trigger a race condition to cause memory corruption.

The issue involves the epoll-watches-epoll case and a concurrent __fput() path that can lead to operations on freed structures.


How to mitigate CVE-2026-46242

Install security update from vendor's repository.

Sources