CVE-2023-53689Network attack vector

Credential theft via reflected license-key script injection

Published Oct 30, 2025 · Updated Nov 17, 2025

Reflected XSS in Nagios Fusion before 4.2.0 allows remote authenticated users to execute script through a crafted license-key URL. The License Information flow returns attacker-controlled URL input without safe output handling; Nagios has not published the affected parameter or code locus. Administrative privileges and a user following the URL are required; execution remains in that browser context but can expose sessions and enable unauthorized administrative actions.

CVSS severity6.0
Medium
EPSS probability0.83%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in Nagios Fusion before 4.2.0 allows remote authenticated users to execute script through a crafted license-key URL. The License Information flow returns attacker-controlled URL input without safe output handling; Nagios has not published the affected parameter or code locus. Administrative privileges and a user following the URL are required; execution remains in that browser context but can expose sessions and enable unauthorized administrative actions.

The record

CVE
CVE-2023-53689
Published
Oct 30, 2025
Updated
Nov 17, 2025
Vendor
Nagios Enterprises, LLC
Product
Nagios Fusion
Classifications
CWE-79, T1566.002
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 30, 2025CVE publishedPublication date reported by the CVE source.
  2. Nov 17, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <4.2.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Nagios Enterprises, LLC · Nagios Fusionversion=0 <4.2.0

Published CVSS scores

4.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
6.0VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1566.002Spearphishing Link

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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