Nagios Fusion up to 4.0.0 Users/Servers Page cross site scripting

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in Nagios Fusion up to 4.0.0. The affected element is an unknown function of the component Users/Servers Page. The manipulation results in cross site scripting. This vulnerability is reported as CVE-2017-20209. The attack can be launched remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic has been found in Nagios Fusion up to 4.0.0. Affected is an unknown part of the component Users/Servers Page. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. CVE summarizes:

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.

The advisory is shared for download at nagios.com. This vulnerability is traded as CVE-2017-20209 since 10/28/2025. The exploitability is told to be easy. It is possible to launch the attack remotely. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1059.007.

Upgrading to version 4.0.1 eliminates this vulnerability. The upgrade is hosted for download at nagios.com.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Fusion 4.0.1

Timelineinfo

10/28/2025 CVE reserved
10/31/2025 +3 days Advisory disclosed
10/31/2025 +0 days VulDB entry created
11/08/2025 +7 days VulDB entry last update

Sourcesinfo

Advisory: nagios.com
Status: Confirmed

CVE: CVE-2017-20209 (🔒)
GCVE (CVE): GCVE-0-2017-20209
GCVE (VulDB): GCVE-100-330732

Entryinfo

Created: 10/31/2025 08:04
Updated: 11/08/2025 00:11
Changes: 10/31/2025 08:04 (69), 11/08/2025 00:11 (11)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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