reDuh was released as part of SensePosts BlackHat USA 2008 talk on tunnelling data in and out of networks. Most external firewalls block all incoming sockets except for port 80/443. reDuh allows an attacker to use the compromised web server as a tunneling proxy into the internal network enviroment. reDuh encodes data into valid HTTP requests, which is then delivered to the server agent, decoded, and redirects the data to the various configured tunnels. reDuh is available in JSP/PHP/ASP.net
