CVE-2026-26987: LibreNMS affected by reflected XSS via email field

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-02-20 · updated 2026-06-17
Weakness: CWE-79

Description

LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 25.12.0 and below are vulnerable to Reflected XSS attacks via email field. This issue has been fixed in version 26.2.0.

Affected products

librenms: before 26.2.0 — fixed in 26.2.0

How to fix

Upgrade to a fixed version: librenms 26.2.0. Check the vendor advisory for mitigations.

References

https://github.com/librenms/librenms/commit/8e626b38ef92e240532cdac2ac7e38706a71208b
https://github.com/librenms/librenms/pull/19038
https://github.com/librenms/librenms/releases/tag/26.2.0
https://github.com/librenms/librenms/security/advisories/GHSA-gqx7-99jw-6fpr

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