Time-of-check Time-of-use (TOCTOU) Affecting kernel-rt-modules-extra package, versions *


Severity

Recommended
low

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.04% (6th 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 IDSNYK-RHEL8-KERNELRTMODULESEXTRA-1924920
  • published23 Nov 2021
  • disclosed15 Nov 2021

Introduced: 15 Nov 2021

CVE-2021-4001  (opens in a new tab)
CWE-367  (opens in a new tab)

How to fix?

There is no fixed version for RHEL:8 kernel-rt-modules-extra.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-rt-modules-extra package and not the kernel-rt-modules-extra package as distributed by RHEL. See How to fix? for RHEL:8 relevant fixed versions and status.

A race condition was found in the Linux kernel's ebpf verifier between bpf_map_update_elem and bpf_map_freeze due to a missing lock in kernel/bpf/syscall.c. In this flaw, a local user with a special privilege (cap_sys_admin or cap_bpf) can modify the frozen mapped address space. This flaw affects kernel versions prior to 5.16 rc2.

CVSS Scores

version 3.1