Securing UltraVNC over Internet with DSM Plugins
June 25th, 2007 by Ben Jim
As promised, for those who are on UltraVNC, securing your VNC over Internet is very easy with a DMS plugin available for encryption. There are currently 3 encryption plugins for UltraVNC, namely MSRC4, ARC4 and AESV2. I’ll demonstrate how to use the MSRC4 plugin as this is well documented on the UltraVNC forum and it’s the most up-to-date in development.
First off all, download the plugin from here and extract the content to your root of your UltraVNC folder (defaulted to “C:\Program Files\UltraVNC”). Note: extract to the root of the folder and not the plugin folder (that’s just a container).
Server Configuration
Now on your UltraVNC Server and you should see MSRC4Plugin in the DSM DSM plugin drop down box.
Check Use and hit the Config button.A MSRC4 Plugin Configuration window will pop up.
You will notice that there aren’t any encryption plugin keys present(naturally since we haven’t created any) so make your first key. Select the default 128 bit hit Gen Key.The configuration tool will close after generating the key and this key will be used from now on on every client computer to allow you to view your server running on that specific key-based encryption. You will notice a new file in your UltraVNC installation folder called rc4.key.
Important: Make sure you bring along this key file (rc4.key) along with your UltraVNC or the client will not be able to interact or see the server.
Client Configuration
Copy this rc4.key to your UltraVNC client’s root directory as with the steps in the Server. When you launch your UltraVNC client, check the box called “Use DSMPlugin” and enter your server’s IP address. Click on connect, enter your password.Done!
