CVE-2025-39663
High
Description
Cross-Site Scripting (XSS) vulnerability in Checkmk's distributed monitoring allows a compromised remote site to inject malicious HTML code into service outputs in the central site. Affecting Checkmk before 2.4.0p14, 2.3.0p39, 2.2.0 and 2.1.0 (eol).
SeverityHigh
CVSS8.4
Exploit probability—
ProductCheckmk
PublishedOct 30, 2025
First seenOct 30, 2025
Weakness typeCWE-80CWE-80
How to fix
Update
- checkmk checkmk2.3.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| checkmk checkmk | 2.0.0 ≤ v < 2.3.0, 2.3.0, 2.4.0 | 2.3.0 |
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