Medium severity · published Oct 30, 2025
CVE-2017-20209
Nagios Fusion < 4.0.1 XSS via Users/Servers Page
6.1
CVSS
0.5%
EPSS
No
On KEV
Description
Nagios Fusion versions prior to 4.0.1 are vulnerable to cross-site scripting (XSS) via the Users and Servers pages. Insufficient validation or escaping of user-supplied input may allow an attacker to inject and execute arbitrary script in the context of a victim's browser.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FU
Fusion · Nagios
before 4.0.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2017-20209
CVE.org
https://www.cve.org/CVERecord?id=CVE-2017-20209
Release Notes
https://www.nagios.com/changelog/nagios-fusion/
Third Party Advisory
https://www.vulncheck.com/advisories/nagios-fusion-xss-via-users-servers-page
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