CVE-2026-26989CWE-79

LibreNMS has Stored XSS in Alert Rule

Medium · published February 20, 2026

CVSS v3.1
4.3
EPSS
0%
Percentile
32.1
In the wild
Unconfirmed
What it is

LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 25.12.0 and below are affected by a Stored Cross-Site Scripting (XSS) vulnerability in the Alert Rules workflow. An attacker with administrative privileges can inject malicious scripts that execute in the browser context of any user who accesses the Alert Rules page. This issue has been fixed in version 26.2.0.

The record
Technical detail
CVSS v3.1
4.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:L/A:L
CVSS v4.0
Not supplied
EPSS
0.00392 · 32.1th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-02-20T01:25Z
EPSS history
Timeline
  • 20 FEB 01:25Z
    LibreNMS has Stored XSS in Alert Rule
    cvelistv5