LibreNMS is an open-source, PHP/MySQL/SNMP-based network monitoring system. A Stored Cross-Site Scripting (XSS) vulnerability in the "Custom OID" tab of a device allows authenticated users to inject arbitrary JavaScript through the "unit" parameter when creating a new OID. This vulnerability can lead to the execution of malicious code in the context of other users' sessions, compromising their accounts and enabling unauthorized actions. This vulnerability is fixed in 24.10.0.