Description
Nagios Fusion versions prior to 4.2.0 contain a reflected cross-site scripting (XSS) vulnerability in the license key configuration flow that can result in execution of attacker-controlled script in the browser of a user who follows a crafted URL. While the application server itself is not directly corrupted by the reflected XSS, the resulting browser compromise can lead to credential/session theft and unauthorized administrative actions.
Affected products
nagios: fusion
References3
- www.nagios.com/products/security/#fusion Vendor Advisory
- www.nagios.com/changelog/nagios-fusion/ Release Notes
- www.vulncheck.com/advisories/nagios-fusion-license-information-… Third Party Advisory
Metrics
- CVSS 3.1
-
4.8
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N - CVSS 4.0
-
6.0
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:N/VA:N/SC:H/SI:H/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 - EPSS — exploit probability
- 1% percentile: 60 · as of 10 November 2026
- CWE
- CWE-79
Could this be exploited in your environment?
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