Medium severity · published Oct 30, 2025
CVE-2023-53689
Nagios Fusion < 4.2.0 License Information Reflected XSS
4.8
CVSS
0.9%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 59% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FU
Fusion · Nagios
before 4.2.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-53689
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-53689
Release Notes
https://www.nagios.com/changelog/nagios-fusion/
Vendor Advisory
https://www.nagios.com/products/security/#fusion
Third Party Advisory
https://www.vulncheck.com/advisories/nagios-fusion-license-information-reflected-xss
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