CVE-2026-9549
Published:June 08, 2026
Updated:June 28, 2026
Stored cross-site scripting in the service discovery active check output in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and all 2.2.0 versions allows an administrator who can configure active or custom checks to inject malicious HTML or JavaScript into check output that executes in the browser of an admin or a user with host read permissions when they run the check on the service discovery page.
Affected Packages
https://github.com/Checkmk/checkmk.git (GITHUB):
Affected version(s) >=v2.3.0 <v2.3.0p48Fix Suggestion:
Update to version v2.3.0p48https://github.com/Checkmk/checkmk.git (GITHUB):
Affected version(s) >=v2.4.0 <v2.4.0p31Fix Suggestion:
Update to version v2.4.0p31https://github.com/Checkmk/checkmk.git (GITHUB):
Affected version(s) >=v2.5.0 <v2.5.0p5Fix Suggestion:
Update to version v2.5.0p5Related Resources (1)
Do you need more information?
Contact UsCVSS v4
Base Score:
4.8
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
HIGH
User Interaction
PASSIVE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
LOW
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
LOW
Subsequent System Availability
NONE
CVSS v3
Base Score:
3.4
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Weakness Type (CWE)
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
EPSS
Base Score:
0.14