CVE-2025-39663: Cross Site Scripting through compromised remote site
Published Oct 30, 2025
·Updated
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 Software
54 affected components
Checkmk Checkmk<2.4.0p14
Checkmk Checkmk>=2.0.0<2.3.0
Checkmk Checkmk=2.3.0
Checkmk Checkmk=2.3.0-p1
Checkmk Checkmk=2.3.0-p10
Checkmk Checkmk=2.3.0-p11
Checkmk Checkmk=2.3.0-p12
Checkmk Checkmk=2.3.0-p13
Checkmk Checkmk=2.3.0-p14
Checkmk Checkmk=2.3.0-p15
Checkmk Checkmk=2.3.0-p16
Checkmk Checkmk=2.3.0-p17
Checkmk Checkmk=2.3.0-p18
Checkmk Checkmk=2.3.0-p19
Checkmk Checkmk=2.3.0-p2
Checkmk Checkmk=2.3.0-p20
Checkmk Checkmk=2.3.0-p21
Checkmk Checkmk=2.3.0-p22
Checkmk Checkmk=2.3.0-p23
Checkmk Checkmk=2.3.0-p24
Checkmk Checkmk=2.3.0-p25
Checkmk Checkmk=2.3.0-p26
Checkmk Checkmk=2.3.0-p27
Checkmk Checkmk=2.3.0-p28
Checkmk Checkmk=2.3.0-p29
Checkmk Checkmk=2.3.0-p3
Checkmk Checkmk=2.3.0-p30
Checkmk Checkmk=2.3.0-p31
Checkmk Checkmk=2.3.0-p32
Checkmk Checkmk=2.3.0-p33
Checkmk Checkmk=2.3.0-p34
Checkmk Checkmk=2.3.0-p35
Checkmk Checkmk=2.3.0-p36
Checkmk Checkmk=2.3.0-p37
Checkmk Checkmk=2.3.0-p38
Checkmk Checkmk=2.3.0-p4
Checkmk Checkmk=2.3.0-p5
Checkmk Checkmk=2.3.0-p6
Checkmk Checkmk=2.3.0-p7
Checkmk Checkmk=2.3.0-p8
Checkmk Checkmk=2.3.0-p9
Checkmk Checkmk=2.4.0
Checkmk Checkmk=2.4.0-p1
Checkmk Checkmk=2.4.0-p10
Checkmk Checkmk=2.4.0-p11
Checkmk Checkmk=2.4.0-p12
Checkmk Checkmk=2.4.0-p13
Checkmk Checkmk=2.4.0-p2
Checkmk Checkmk=2.4.0-p3
Checkmk Checkmk=2.4.0-p4
Checkmk Checkmk=2.4.0-p5
Checkmk Checkmk=2.4.0-p6
Checkmk Checkmk=2.4.0-p7
Checkmk Checkmk=2.4.0-p9
Event History
Oct 30, 2025
CVE Published
via MITRE·10:43 AM
Data Sourced
via MITRE·10:43 AM
DescriptionWeakness
Data Sourced
via NVD·11:15 AM
DescriptionSeverityWeaknessAffected Software
Frequently Asked Questions
1
What is the severity of CVE-2025-39663?
CVE-2025-39663 is classified as a high severity Cross-Site Scripting (XSS) vulnerability.
2
How do I fix CVE-2025-39663?
To fix CVE-2025-39663, upgrade Checkmk to version 2.4.0p14 or later.
3
What types of attacks can CVE-2025-39663 facilitate?
CVE-2025-39663 can facilitate the injection of malicious HTML code through compromised remote sites.
4
Which versions of Checkmk are affected by CVE-2025-39663?
CVE-2025-39663 affects Checkmk versions prior to 2.4.0p14, including 2.3.0p39, 2.2.0, and 2.1.0.
5
What is the impact of CVE-2025-39663 on users?
The impact of CVE-2025-39663 on users includes potential exposure to malicious content and exploits via service outputs.