CVE-2025-64999CWE-79

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

High · published February 26, 2026

CVSS v4.0
7.3
EPSS
0%
Percentile
5.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
7.3 · HIGH
Vector
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
EPSS
0.00168 · 5.9th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-02-26T10:26Z
EPSS history
Timeline
  • 26 FEB 10:26Z
    Cross-site scripting in HTML logs of Synthetic Monitoring test services
    cvelistv5