What’s Vulnerable › Vulnerabilities
CVE-2026-9549: Fix XSS in service discovery active check output
- Severity: medium (CVSS 4.8 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.1% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-06-08 · updated 2026-10-23
- Weakness: CWE-79
Description
Stored cross-site scripting in the service discovery active check output in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and all 2.2.0 versions allows an administrator who can configure active or custom checks to inject malicious HTML or JavaScript into check output that executes in the browser of an admin or a user with host read permissions when they run the check on the service discovery page.
Affected products
- Checkmk GmbH Checkmk: 2.2.0, 2.2.0-b1, 2.2.0-b2, 2.2.0-b3, 2.2.0-b4, 2.2.0-b5 (+150)
References
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