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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-08 13:02 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
URL Tags
https://checkmk.com/werk/17993 vendor-advisory
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)
    cpe:2.3:a:checkmk:checkmk:*:*:*:*:*:*:*:*
    cpe:2.3:a:checkmk:checkmk:*:*:*:*:*:*:*:*
    cpe:2.3:a:checkmk:checkmk:*:*:*:*:*:*:*:*
    cpe:2.3:a:checkmk:checkmk:2.2.0:*:*:*:*:*:*:*
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