Use After Free in Linux kernel - CVE-2026-23275
Published: March 20, 2026
Vulnerability identifier: #VU124172
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-23275
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to execute arbitrary code or escalate privileges.
The vulnerability exists due to a use-after-free in io_uring component when handling task work flags manipulation during ring resizing. A local user can exploit this by triggering specific io_uring operations that manipulate task work flags while ring resizing occurs, leading to access to previously freed memory.
The vulnerability specifically affects configurations using DEFER_TASKRUN mode, which supports ring resizing. Exploitation requires the ability to create and manipulate io_uring rings, typically available to unprivileged users in modern Linux distributions.
How to mitigate CVE-2026-23275
Install security update from vendor's repository.