CVE-2021-40904: checkmk Incorrect Default Permissions
Vulnerability summary
CVE-2021-40904 is a high (CVSS 8.8) Incorrect Default Permissions vulnerability in checkmk. EPSS estimates a 3.69% chance of exploitation in the next 30 days, higher than 89.5% of scored vulnerabilities. 1 public exploit is recorded.
Timeline
- 25-03-2022PublishedVulnerability first disclosed.
- 09-07-2026Last modifiedVulnerability information updated.
Description
The web management console of CheckMK Raw Edition (versions 1.5.0 to 1.6.0) allows a misconfiguration of the web-app Dokuwiki (installed by default), which allows embedded php code. As a result, remote code execution is achieved. Successful exploitation requires access to the web management interface, either with valid credentials or with a hijacked session by a user with the role of administrator.
CVSS metrics
3 scores · 2 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated8.8HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS trend
Probability
3.69%
Chance of exploitation in the next 30 days
Percentile
90%
Versus all other CVEs
30-day change
0.00 pp
From 3.69% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundCve 2021 40904
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Checkmk1 product
- checkmk≥ 1.5.0, < 1.6.0
Ubuntu1 product
- check-mkAll versions (No fix recorded)
2 vendors · 2 products