Vulnerability · Published Aug 12, 2026 · Assigned by VulnCheck
CVE-2026-48552Nagios Core / XI DOM-based XSS via jsonquery.js
Medium 5.4
In plain English
A medium-severity cross-site scripting in Nagios Core from Nagios Enterprises, LLC.. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | nagios4 | 4.4.6-4+deb12u2 | DEBIAN-CVE-2026-48552 |
| Debian:13 | nagios4 | 4.4.6-4.1+deb13u2 | DEBIAN-CVE-2026-48552 |
| Debian:14 | nagios4 | 4.5.14+ds-1 | DEBIAN-CVE-2026-48552 |
| Ubuntu:22.04:LTS | nagios4 | no fix listed | UBUNTU-CVE-2026-48552 |
| Ubuntu:24.04:LTS | nagios4 | no fix listed | UBUNTU-CVE-2026-48552 |
| Ubuntu:26.04:LTS | nagios4 | no fix listed | UBUNTU-CVE-2026-48552 |
| Ubuntu:26.10 | nagios4 | no fix listed | UBUNTU-CVE-2026-48552 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Nagios Enterprises, LLC. | Nagios Core | 0 – before 4.5.14 |
| Nagios Enterprises, LLC. | Nagios XI | 0 – before 2026R1.7 |
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
References
- Security Disclosures vendor-advisory, patch
- Changelog release-notes
- https://www.vulncheck.com/advisories/nagios-core-xi-dom-based-xss-via-jsonquery-js third-party-advisory