CVE-2021-47694: Nagios XI < 5.8.6 Core Config Manager (CCM) Reflected XSS via Test Command

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-10-30 · updated 2026-06-17
Weakness: CWE-79

Description

The Core Config Manager (CCM) in Nagios XI versions prior to CCM 3.1.4 / Nagios XI 5.8.6 contains a reflected cross-site scripting (XSS) vulnerability via the Test Command functionality. 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.

Affected products

Nagios XI: before 5.8.6 — fixed in 5.8.6

How to fix

Upgrade to a fixed version: Nagios XI 5.8.6. Check the vendor advisory for mitigations.

References

https://www.nagios.com/changelog/nagios-xi/
https://www.vulncheck.com/advisories/nagios-xi-ccm-reflected-xss-via-test-command

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