CVE-2021-20321

Updated: 2026-02-27 00:13:30.384874

Description:

A race condition accessing file object in the Linux kernel OverlayFS subsystem was found in the way users do rename in specific way with OverlayFS. A local user could use this flaw to crash the system.


Links NIST CIRCL RHEL Ubuntu

Severity

Severity Score
CVSS Version 2.x MEDIUM 4.7
CVSS Version 3.x MEDIUM 4.7

Status

OS name Project name Version Score Severity Status Errata Last updated

Statement

AlmaLinux 9.2 ESU kernel 5.14.0 4.7 MEDIUM Ignored 2023-11-21 04:12:22 This issue is a local-only, high‑complexity race condition in OverlayFS’s rename path that resul...
CentOS 6 ELS kernel 2.6.32 4.7 MEDIUM Not Vulnerable 2022-03-30 18:48:16 Not affected: This CVE targets the Linux kernel’s OverlayFS subsystem, but OverlayFS was not inclu...
CentOS 7 ELS kernel 3.10.0 4.7 MEDIUM Released CLSA-2024:1720468480 2024-07-23 17:33:17
CentOS 8.4 ELS kernel 4.18.0 4.7 MEDIUM Released CLSA-2022:1651145959 2022-04-28 15:58:51
CentOS 8.5 ELS kernel 4.18.0 4.7 MEDIUM Released CLSA-2022:1644934107 2022-03-10 14:51:55
CloudLinux 6 ELS kernel 2.6.32 4.7 MEDIUM Not Vulnerable 2022-03-30 18:48:16
Oracle Linux 6 ELS kernel 2.6.32 4.7 MEDIUM Not Vulnerable 2022-03-30 18:48:16 Not affected: This CVE targets the Linux kernel’s OverlayFS subsystem, but OverlayFS was not inclu...
RHEL 7 ELS kernel 3.10.0 4.7 MEDIUM Released CLSA-2025:1750353839 2025-06-20 00:28:24
Ubuntu 16.04 ELS linux-hwe 4.15.0 4.7 MEDIUM Already Fixed 2023-07-17 11:09:25
Ubuntu 16.04 ELS linux 4.4.0 4.7 MEDIUM Released CLSA-2023:1690395161 2023-07-26 17:15:26
Total: 11