pfSense Plus < 26.07 / CE < 2.9.0 Stored XSS via firewall_schedule_edit.php

pfSense Plus before 26.07 and CE before 2.9.0 allow authenticated users with the Firewall: Schedules: Edit privilege to inject arbitrary JavaScript via the descr parameter in /firewall_schedule_edit.php. The schedule description is stored without HTML sanitization and subsequently inserted into an HTML attribute value in /firewall_rules.php with only single-quote escaping applied, permitting double-quote breakout. The payload executes in the browser of any user with the Firewall: Rules privilege who views the rules list with the affected schedule attached.