4.4

CVE-2021-4037: Kernel: security regression for cve-2018-13405

Modified
AliasesUBUNTU-CVE-2021-4037DEBIAN-CVE-2021-4037
Published 24-08-2022Last modified 14-10-2026

Vulnerability summary

CVE-2021-4037 is a medium (CVSS 4.4) Improper Access Control vulnerability in debian debian_linux. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 27.2% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 4.4, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
4.4/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.34%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 23 · Related 17
DLA-3173-1DSA-5257-1RHSA-2022:1975RHSA-2022:1988RHSA-2022:4829RHSA-2022:4835

Timeline

  1. 24-08-2022
    PublishedVulnerability first disclosed.
  2. 14-10-2026
    Last modifiedVulnerability information updated.

Description

A vulnerability was found in the fs/inode.c:inode_init_owner() function logic of the LInux kernel that allows local users to create files for the XFS file-system with an unintended group ownership and with group execution and SGID permission bits set, in a scenario where a directory is SGID and belongs to a certain group and is writable by a user who is not a member of this group. This can lead to excessive permissions granted in case when they should not. This vulnerability is similar to the previous CVE-2018-13405 and adds the missed fix for the XFS.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.34%

Chance of exploitation in the next 30 days

Percentile

27%

Versus all other CVEs

30-day change

Increase +0.02 pp

From 0.31% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu60 products
  • linuxAll versions (No fix recorded) | < 4.4.0-234.268 | < 4.15.0-166.174 | < 5.4.0-92.103
  • linux-aws< 4.4.0-1113.119 | < 4.4.0-1151.166 | < 4.15.0-1118.125 | < 5.4.0-1061.64
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11< 5.11.0-1023.24~20.04.1
  • linux-aws-5.3All versions (No fix recorded)
Debian2 products
Linux2 products

3 vendors · 64 products

References

18 links
Show all 18 references