5.5

CVE-2021-38203: linux linux_kernel Improper Locking

CVSS: 5.5v3.1MediumModified
AliasesUBUNTU-CVE-2021-38203DEBIAN-CVE-2021-38203
Published 08-08-2021Last modified 04-08-2024
Open JSON

Vulnerability summary

CVE-2021-38203 is a medium (CVSS 5.5) Improper Locking vulnerability in linux linux_kernel. EPSS estimates a 0.36% chance of exploitation in the next 30 days, higher than 28.8% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
32/100
0100
Medium · default modelHow is this calculated?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.36%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github

Advisory lineage

Upstream 0 · Downstream 1 · Related 1
USN-5096-1

Timeline

  1. 08-08-2021
    PublishedVulnerability first disclosed.
  2. 04-08-2024
    Last modifiedVulnerability information updated.

Description

btrfs in the Linux kernel before 5.13.4 allows attackers to cause a denial of service (deadlock) via processes that trigger allocation of new system chunks during times when there is a shortage of free space in the system space_info.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.36%

Chance of exploitation in the next 30 days

Percentile

29%

Versus all other CVEs

30-day change

0.00 pp

From 0.36% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.36%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • githubUnverified

    Linux

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Ubuntu22 products
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.3All versions (No fix recorded)
  • linux-aws-5.8All versions (No fix recorded)
  • linux-azureAll versions (No fix recorded)
  • linux-azure-5.3All versions (No fix recorded)
Netapp4 products
Debian1 product
  • linux< 5.14.6-1
Linux1 product

4 vendors · 28 products

References

8 links