CVE-2026-84192

High

Description

LibreNMS before 26.3.1 contains a stored cross-site scripting vulnerability in legacy PHP templates that output SNMP-sourced and syslog-sourced data without escaping. An attacker who controls a monitored network device can inject arbitrary JavaScript through SNMP interface descriptions or syslog program fields that executes when authenticated users view affected pages.

SeverityHigh

CVSS7.1

Exploit probability—

ProductLibrenms/librenms

PublishedSep 1, 2026

First seenSep 1, 2026

Weakness typeCWE-79Cross-site scripting (XSS)

How to fix

Update

librenms/librenms26.5.0 or later

Vendor advisories

github.com/librenms/librenms/security/advisories/GHSA-7w8c-qgxg-m7jx

Affected products

Product	Affected versions	Fixed in
librenms/librenmsPackagist	v < 26.5.0	26.5.0

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