CVE-2025-64999highCWE-79

CVE-2025-64999: high-severity vulnerability in Checkmk

Cross-site scripting in HTML logs of Synthetic Monitoring test services

Published · Updated

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.3epss 0.2%
Improper neutralization of input in Checkmk versions 2.4.0 before 2.4.0p22, and 2.3.0 before 2.3.0p43 allows an attacker that can manipulate a host's check output to inject malicious JavaScript into the Synthetic Monitoring HTML logs, which can then be accessed via a crafted phishing link.
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:L/SA:N
Affected products
Checkmk GmbH · Checkmk