XSS in Librenms
CVE-2026-26992
LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. In versions 26.1.1 and below, the port group name is not sanitized, allowing attackers with admin privileges to perform Stored Cross-Site Scripting (XSS) attacks. When a user adds a port group, an HTTP POST request is sent to the Request-URI "/port-groups". The name of the newly created port group is stored in the value of the name parameter. After the port group is created, the entry is displayed along with relevant buttons such as Edit and Delete. This issue has been fixed in version 26.2.0.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (22.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 22.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- Librenms — versions < 26.2.0
Weakness classification (CWE)
References
- github.com/librenms/librenms/security/advisories/GHSA-93fx-g747-695x (Exploit, Third Party Advisory)
- github.com/librenms/librenms/pull/19042 (Issue Tracking)
- github.com/librenms/librenms/commit/882fe6f90ea504a3732f83caf89bba7850a5699f (Patch)
- github.com/librenms/librenms/releases/tag/26.2.0 (Product, Release Notes)
Frequently asked questions
- What is CVE-2026-26992?
- CVE-2026-26992 is a medium-severity vulnerability in Librenms, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2026-02-20.
- How severe is CVE-2026-26992?
- Medium severity. CVSS v3 base score is 4.8 out of 10.