CVE-2026-84191

LibreNMS before 26.5.0 contains stored cross-site scripting vulnerabilities in VRF display pages where mplsVpnVrfDescription, vrf_name, and mplsVpnVrfRouteDistinguisher fields from SNMP polling are rendered without sanitization. Attackers controlling a monitored network device can inject arbitrary JavaScript through SNMP responses that executes in the browser of any user viewing VRF-related pages.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/librenms/librenms/security/advisories/GHSA-g993-wffj-m3gv
https://www.vulncheck.com/advisories/librenms-before-26.5.0-stored-xss-via-snmp-vrf-fields

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-01 12:17

Updated : 2026-09-08 20:18

NVD link : CVE-2026-84191

Mitre link : CVE-2026-84191

CVE.ORG link : CVE-2026-84191

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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