MEDIUM · 4.3

CVE-2026-26989

LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 25.12.0 and below are affected by a Stored Cross-Site Scripting (XSS) vulnerability in the Alert Rules workflow. ...

Vulnerability Description

LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 25.12.0 and below are affected by a Stored Cross-Site Scripting (XSS) vulnerability in the Alert Rules workflow. An attacker with administrative privileges can inject malicious scripts that execute in the browser context of any user who accesses the Alert Rules page. This issue has been fixed in version 26.2.0.

CVSS Score

4.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:L/A:L
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
LOW

Affected Products

VendorProductVersions
LibrenmsLibrenms< 26.2.0

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-26989?

CVE-2026-26989 is a vulnerability with a CVSS score of 4.3 (MEDIUM). LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 25.12.0 and below are affected by a Stored Cross-Site Scripting (XSS) vulnerability in the Alert Rules workflow. ...

How severe is CVE-2026-26989?

CVE-2026-26989 has been rated MEDIUM with a CVSS base score of 4.3/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-26989?

Check the references section above for vendor advisories and patch information. Affected products include: Librenms Librenms.