Hotspot Shield runs a webserver with a static IP address 127.0.0.1 and port 895. The web server uses JSONP and hosts sensitive information including configuration. User controlled input is not sufficiently filtered: an unauthenticated attacker can send a POST request to /status.js with the parameter func=$_APPLOG.Rfunc and extract sensitive information about the machine, including whether the user is connected to a VPN, to which VPN he/she is connected, and what is their real IP address.