XSS in Checkmk
CVE-2026-3466
Insufficient sanitization of dashboard dashlet title links in Checkmk 2.2.0 (EOL), Checkmk 2.3.0 before 2.3.0p46, Checkmk 2.4.0 before 2.4.0p25, and Checkmk 2.5.0 (beta) before 2.5.0 allows an attacker with dashboard creation privileges to perform stored cross-site scripting (XSS) attacks by tricking a victim into clicking a crafted dashlet title link on a shared dashboard.
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.002 (13.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
Affected products
- Checkmk — versions 2.2.0, 2.3.0, 2.4.0
- Checkmk Gmbh — versions 2.2.0, 2.3.0, 2.4.0
Weakness classification (CWE)
References
- security@checkmk.com (vendor-advisory, Vendor Advisory)
- security@checkmk.com (vendor-advisory)
- security@checkmk.com (Third Party Advisory, Release Notes, third-party-advisory)
Frequently asked questions
- What is CVE-2026-3466?
- CVE-2026-3466 is a medium-severity vulnerability in Checkmk, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-04-07.
- How severe is CVE-2026-3466?
- Medium severity. CVSS v3 base score is 5.4 out of 10.