CVE-2026-26991

LibreNMS vulnerable to Stored Cross-site Scripting through unsanitized /device-groups name

CVSS 5.1 MEDIUMEPSS 0.2%CWE-79

Vexday Risk Score

13Low

SSVC decision (CISA)

Track

No exploitation signal → monitor

CVSS 5.1EPSS 0.2%KEV nãoPoC —Nuclei —Metasploit —Patch —

Lifecycle

20 Feb 2026Published on NVD

Recommendation: Monitor — no exploitation signal at the moment.

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.

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

Affected products

librenms · librenms

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References

https://github.com/librenms/librenms/commit/64b31da444369213eb4559ec1c304ebfaa0ba12c https://github.com/librenms/librenms/pull/19041 https://github.com/librenms/librenms/releases/tag/26.2.0 https://github.com/librenms/librenms/security/advisories/GHSA-5pqf-54qp-32wx