CVE-2026-26991

medium

Description

LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. In versions 26.1.1 and below, the device group name is not sanitized, allowing attackers with admin privileges to perform Stored Cross-Site Scripting (XSS) attacks. When a user adds a device group, an HTTP POST request is sent to the Request-URI "/device-groups". The name of the newly created device group is stored in the value of the name parameter. After the device group is created, the entry is displayed along with relevant buttons such as Rediscover Devices, Edit, and Delete. This issue has been fixed in version 26.2.0.

References

https://github.com/librenms/librenms/security/advisories/GHSA-5pqf-54qp-32wx

https://github.com/librenms/librenms/releases/tag/26.2.0

https://github.com/librenms/librenms/pull/19041

https://github.com/librenms/librenms/commit/64b31da444369213eb4559ec1c304ebfaa0ba12c

Details

Source: Mitre, NVD

Published: 2026-02-20

Updated: 2026-02-20

Risk Information

CVSS v2

Base Score: 4.7

Vector: CVSS2#AV:N/AC:L/Au:M/C:P/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 4.8

Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

Severity: Medium

CVSS v4

Base Score: 5.1

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

Severity: Medium

EPSS

EPSS: 0.00007