IPFire < v2.29 Stored XSS via Default Country Search

IPFire versions prior to 2.29 (Core Update 198) contain a stored cross-site scripting (XSS) vulnerability that allows an authenticated attacker to inject arbitrary JavaScript code through the pienumber parameter when updating the firewall country search defaults. When a user updates the default values for the firewall country search, the application issues an HTTP POST request to /cgi-bin/logs.cgi/firewalllogcountry.dat and the default number of countries to display is provided in the pienumber parameter. The value of this parameter is stored and later rendered in the web interface without proper sanitation or encoding, allowing injected scripts to execute in the context of other users who view the affected firewall country search settings.