CVE-2026-20915: Stored cross-site scripting (XSS) in Checkmk version 2.5.0 (beta) before 2.5.0b2 allows authenticated users with permission to create pending changes to inject…

PriorityP424medium5.4CVSS 3.1

AVNACLPRLUIRSCCLILAN

EPSS

0.15%

4.3th percentile

Stored cross-site scripting (XSS) in Checkmk version 2.5.0 (beta) before 2.5.0b2 allows authenticated users with permission to create pending changes to inject malicious JavaScript into the Pending Changes sidebar, which will execute in the browsers of other users viewing the sidebar.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
checkmk	checkmk	—	—
checkmk_gmbh	checkmk	>= 2.5.0b1 < 2.5.0b2	2.5.0b2

CVSS provenance

nvdv3.15.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

nvdv4.08.5HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:L/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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