XSS in Nagios Xi
CVE-2021-47691
The Core Config Manager (CCM) in Nagios XI versions prior to CCM 3.1.1 / Nagios XI 5.8.2 contains multiple cross-site scripting (XSS) vulnerabilities via the Services page affecting the config_name and service_description fields. 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.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (33.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 33.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
Weakness classification (CWE)
References
- www.nagios.com/changelog/nagios-xi/ (release-notes, Release Notes, patch)
- www.vulncheck.com/advisories/nagios-xi-ccm-xss-via-services-page (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2021-47691?
- CVE-2021-47691 is a medium-severity vulnerability in Nagios Xi, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2025-10-30.
- How severe is CVE-2021-47691?
- Medium severity. CVSS v3 base score is 5.4 out of 10.