What is CVE-2025-58121?

CVE-2025-58121 is a medium-severity vulnerability in Checkmk, classified under Improper Handling of Insufficient Permissions or Privileges. CVSS score: 5.4/10. Published 2025-11-18.

How severe is CVE-2025-58121?

Medium severity. CVSS v3 base score is 5.4 out of 10.

Vulnerability in Checkmk

CVE-2025-58121

Insufficient permission validation on multiple REST API endpoints in Checkmk 2.2.0, 2.3.0, and 2.4.0 before version 2.4.0p16 allows low-privileged users to perform unauthorized actions or obtain sensitive information

Published 2025-11-18 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (8.7th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 9th percentile — 8.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

Checkmk — versions 2.4.0
Checkmk Gmbh — versions 2.4.0, 2.3.0, 2.2.0

Weakness classification (CWE)

CWE-280 — Improper Handling of Insufficient Permissions or Privileges

References

checkmk.com/werk/18983 (Vendor Advisory)

Frequently asked questions

What is CVE-2025-58121?: CVE-2025-58121 is a medium-severity vulnerability in Checkmk, classified under Improper Handling of Insufficient Permissions or Privileges. CVSS score: 5.4/10. Published 2025-11-18.
How severe is CVE-2025-58121?: Medium severity. CVSS v3 base score is 5.4 out of 10.