Directory traversal vulnerability in Pro Chat Rooms 3.0.2 allows remote authenticated users to select an arbitrary local PHP script as an avatar via a .. (dot dot) in the avatar parameter, and cause other users to execute this script by using sendData.php to send a message to (1) an individual user or (2) a room, leading to cross-site request forgery (CSRF), cross-site scripting (XSS), or other impacts.