What is CVE-2026-26987?

CVE-2026-26987 is a medium-severity vulnerability in Librenms, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-02-20.

How severe is CVE-2026-26987?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Librenms

CVE-2026-26987

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.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2026-02-20 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.004 (27.3th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 27.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001

Affected products

Librenms — versions < 26.2.0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/librenms/librenms/security/advisories/GHSA-gqx7-99jw-6fpr (Exploit, Third Party Advisory)
github.com/librenms/librenms/pull/19038 (Issue Tracking)
github.com/librenms/librenms/commit/8e626b38ef92e240532cdac2ac7e38706a71208b (Patch)
github.com/librenms/librenms/releases/tag/26.2.0 (Product, Release Notes)

Frequently asked questions

What is CVE-2026-26987?: CVE-2026-26987 is a medium-severity vulnerability in Librenms, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-02-20.
How severe is CVE-2026-26987?: Medium severity. CVSS v3 base score is 6.1 out of 10.