CVE-2026-56126: Netgate Pfsense CE

Medium severity, CVSS 5.4. EPSS: 1.1% chance of exploitation in the next 30 days.

pfSense Plus before 26.07 and CE before 2.9.0 allow authenticated users with the Status: Monitoring privilege to inject arbitrary JavaScript via graph configuration parameters in /status_monitoring.php. Multiple POST parameters including graph-left, graph-right, time-period, resolution, start-date, end-date, start-time, end-time, graph-type, invert, and refresh-interval are concatenated and written to the global pfSense XML configuration without sanitization, then echoed unsanitized into a JavaScript string context on page render. Because the setting is stored in the global configuration, the payload executes in the browser of every user who visits the Status: Monitoring page.

Affected products

• Netgate Pfsense CE: before 2.9.0 (fixed in 2.9.0)
• Netgate Pfsense Plus: before 26.07 (fixed in 26.07)

Published 2026-09-03. Last modified 2026-09-09.