Stored Cross-Site Scripting Vulnerability in LibreNMS Network Monitoring Tool
CVE-2026-26989

4.3MEDIUM

Key Information:

Vendor

Librenms

Status
Librenms
Vendor
CVE Published:
20 February 2026

What is CVE-2026-26989?

LibreNMS, an automatic network monitoring tool based on PHP/MySQL/SNMP, presents a Stored Cross-Site Scripting (XSS) vulnerability within its Alert Rules functionality. Attackers with administrative access can maliciously inject scripts that will execute in the browser of any user who visits the Alert Rules page. This security flaw has been resolved in version 26.2.0, emphasizing the need for users to upgrade to maintain system integrity.

Affected Version(s)

librenms < 26.2.0

References

https://github.com/librenms/librenms/security/advisories/...
x_refsource_CONFIRM
https://github.com/librenms/librenms/pull/19039
x_refsource_MISC
https://github.com/librenms/librenms/commit/087608cf9f851...
x_refsource_MISC

CVSS V3.1

Score:
4.3
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
High
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.