Segments

SSH Tunneling isn't new to the show, we've done it before over DNS or in conjunction with VNC. Today we're looking at two SSH tricks for tunneling just about any traffic.

First up, ssh -D. The -D option specified a local "e;Dynamic"e; application-level port forwarding. Any connection made to the specified port goes through the tunnel as a SOCKS4 or SOCKS5 proxy. Perfect for secure web browsing as demonstrated with Firefox in this segment.

ssh -D 8080 user@server

Second, ssh -L. The -L option enables port forwarding. Using this option tells the SSH client to listen to traffic on a specified port and forward it along through the tunnel. The server receives this data and points it to the specified destination, whether it be on the destination network or otherwise. In our example we use the -L option to securely connect to an open IRC server.

ssh user@server -L local-listen-port:destination-ip:destination-port

For more SSH-fu check out the ssh man page or Linux Journal's interesting series on 101 uses of openssh.

The age old scheme for bypassing restrictive firewalls, like those that block sites at school or work, has been to use a web proxy. Of course this is followed up by the network administrator blocking all mainstream proxies. But what if you could run your own? Well, you can and it's really freaking easy. In this segment Darren demonstrates PHProxy

On episode 612 we demonstrated a tool, asleap, designed to crack MS-CHAPv2, the authentication protocol commonly found in Microsoft PPTP VPNs. The final demo was unsuccessful due to the encoding of the handshake and response sniffed by Wireshark. Viewer Sc00bz was kind enough to post a PHP script that accepts the challenge, response and username and provides you with the proper asleap command to run with the properly encoded byte sequences. Sc00bz has well documented the code, which lives now on this Hak5 forum thread. Thanks Sc00bz!

A Virtual Appliance can be though of as a software image containing a supporting stack designed to run inside a virtual machine. A quick look at vmware's virtual appliance directory shows that there are hundreds of applications that can be quickly and easily deployed. In this segment I take the Dimdim open source virtual appliance, designed for vmware, and deploy it with VirtualBox (just becasue I can).