CVE-2025-39663: Cross-Site Scripting (XSS) vulnerability in Checkmk's distributed monitoring allows a compromised remote site to inject malicious HTML code into service…

PriorityP335high8.4CVSS 3.1

AVNACLPRHUIRSCCHIHAH

EPSS

0.55%

41.8th percentile

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

7 ranges

Vendor	Product	Version range	Fixed in
checkmk	checkmk	—	—
checkmk	checkmk	—	—
checkmk	checkmk	>= 2.0.0 < 2.3.0	2.3.0
checkmk_gmbh	checkmk	—	—
checkmk_gmbh	checkmk	—	—
checkmk_gmbh	checkmk	>= 2.3.0 < 2.3.0p39	2.3.0p39
checkmk_gmbh	checkmk	>= 2.4.0 < 2.4.0p14	2.4.0p14

CVSS provenance

nvdv3.18.4HIGHCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H

nvdv4.08.5HIGHCVSS: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

osv8.5HIGH

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