Description
Cross-Site Scripting (XSS) vulnerability in Checkmk's distributed monitoring allows a compromised remote site to inject malicious HTML code into service outputs in the central site. Affecting Checkmk before 2.4.0p14, 2.3.0p39, 2.2.0 and 2.1.0 (eol).
Affected products
checkmk: checkmk
References4
- checkmk.com/werk/17998 Vendor Advisory
- github.com/sbaresearch/advisories/tree/82fd27e4570433464c30b351… ExploitThird Party Advisory
- seclists.org/fulldisclosure/2025/Nov/0 ExploitMailing ListThird Party Advisory
- github.com/sbaresearch/advisories/tree/82fd27e4570433464c30b351… ExploitThird Party Advisory
Metrics
- CVSS 3.1
-
8.4
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H - CVSS 4.0
-
8.5
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 49 · as of 10 November 2026
- CWE
- CWE-80CWE-79
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