CVE-2026-9549 (GCVE-0-2026-9549)

Vulnerability from cvelistv5 – Published: 2026-06-08 12:07 – Updated: 2026-06-08 13:02
VLAI?
Title
Fix XSS in service discovery active check output
Summary
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.
Severity ?
4.8 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
Checkmk GmbH Checkmk Affected: 2.5.0 , < 2.5.0p5 (semver)
Affected: 2.4.0 , < 2.4.0p31 (semver)
Affected: 2.3.0 , < 2.3.0p48 (semver)
Affected: 2.2.0 (semver)
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.