Time-of-check Time-of-use (TOCTOU) Affecting kernel-devel-matched package, versions *


Severity

Recommended
low

Based on CentOS security rating.

Threat Intelligence

EPSS
0.02% (4th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications

Snyk Learn

Learn about Time-of-check Time-of-use (TOCTOU) vulnerabilities in an interactive lesson.

Start learning
  • Snyk IDSNYK-CENTOS10-KERNELDEVELMATCHED-15904356
  • published5 Apr 2026
  • disclosed3 Apr 2026

Introduced: 3 Apr 2026

NewCVE-2026-23436  (opens in a new tab)
CWE-367  (opens in a new tab)

How to fix?

There is no fixed version for Centos:10 kernel-devel-matched.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-devel-matched package and not the kernel-devel-matched package as distributed by Centos. See How to fix? for Centos:10 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

net: shaper: protect from late creation of hierarchy

We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections.

The netdev may get unregistered in between the time we take the ref and the time we lock it. We may allocate the hierarchy after flush has already run, which would lead to a leak.

Take the instance lock in pre- already, this saves us from the race and removes the need for dedicated lock/unlock callbacks completely. After all, if there's any chance of write happening concurrently with the flush - we're back to leaking the hierarchy.

We may take the lock for devices which don't support shapers but we're only dealing with SET operations here, not taking the lock would be optimizing for an error case.

CVSS Base Scores

version 3.1