XSS in Nagios Enterprises, Llc. Core
CVE-2026-48552
Nagios Core before 4.5.14 and Nagios XI before 2026R1.7 are vulnerable to DOM-based cross-site scripting in jsonquery.js. Unencoded JSON string values reflected from stored fields are inserted into the DOM without sanitization, allowing attackers to run arbitrary JavaScript in the 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: 0.003 (19.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 19th percentile — 19.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- Nagios Enterprises, Llc. Core — versions 0
- Nagios Enterprises, Llc. Xi — versions 0
Weakness classification (CWE)
References
- www.nagios.com/security-disclosures/nagios-core/ (vendor-advisory, patch)
- github.com/NagiosEnterprises/nagioscore/blob/master/Changelog (release-notes)
- www.vulncheck.com/advisories/nagios-core-xi-dom-based-xss-via-jsonquery-js (third-party-advisory)
Frequently asked questions
- What is CVE-2026-48552?
- CVE-2026-48552 is a medium-severity vulnerability in Nagios Enterprises, Llc. Core, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-08-12.
- How severe is CVE-2026-48552?
- Medium severity. CVSS v3 base score is 5.4 out of 10.