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 malicious JavaScript into the Pending Changes sidebar, which will execute in the browsers of other users viewing the sidebar.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://checkmk.com/werk/19526	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:checkmk:checkmk:2.5.0:b1:*:*:*:*:*:*

History

02 Apr 2026, 12:06

Type	Values Removed	Values Added
CPE		cpe:2.3:a:checkmk:checkmk:2.5.0:b1::::::
References	~~() https://checkmk.com/werk/19526 -~~	() https://checkmk.com/werk/19526 - Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.4
First Time		Checkmk Checkmk checkmk

31 Mar 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-31 15:16

Updated : 2026-04-02 12:06

NVD link : CVE-2026-20915

Mitre link : CVE-2026-20915

CVE.ORG link : CVE-2026-20915

JSON object : View

Products Affected

checkmk

checkmk

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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