WP Booking System < 2.1.0.1 - Unauthenticated Stored XSS via X-Forwarded-For Header

The WP Booking System WordPress plugin before 2.1.0.1 does not sanitise and escape a client-controllable request value before storing it and later outputting it in an administration screen, allowing unauthenticated attackers to perform Stored Cross-Site Scripting attacks that execute in the session of an administrator who views the stored data.