CVE-2026-45694: Librenms

Medium severity, CVSS 5.4. EPSS: 0.2% chance of exploitation in the next 30 days.

LibreNMS is a network monitoring system. In versions up to and including 26.4.0, the Proxmox application view is vulnerable to reflected cross-site scripting through the user-supplied instance and vmid GET parameters, which are reflected into the page title without adequate encoding. The parameters are placed into the page title with only strip_tags applied, and the title is then written into an inline document.title assignment through string interpolation, so a single quote terminates the JavaScript string and the remaining input runs as script. An attacker who lures an authenticated user into following a crafted link can execute script in that user's session, enabling actions such as theft of session data. This issue is fixed in version 26.5.0.

Affected products

• Librenms Librenms: before 26.5.0 (fixed in 26.5.0)

Published 2026-08-26. Last modified 2026-09-09.