PT-2026-47288 · Checkmk Gmbh · Checkmk

Published 2026-06-08 · Updated 2026-06-08 · CVE-2026-9549

Mitre

CVSS v4.0

4.8

Medium

Base vector

AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N

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.

Fix

XSS

Weakness Enumeration

CWE-79

Related Identifiers

CVE-2026-9549

Affected Products

Checkmk

References · 2

• https://nvd.nist.gov/vuln/detail/CVE-2026-9549 · Security Note
• https://checkmk.com/werk/17993 · Vendor Advisory