How to disable USB sticks and limit access to USB storage devices on Windows systems

by Hannes Schmidt

USB storage - a possible security risk?
Decent IT administrators secure their networks behind firewalls. They install mail filters on their SMTP servers and deploy anti-virus software on all client workstations. But securing the network is not sufficient -- what happens if the users bring their own USB memory sticks and connect them to the computers at their office? A 1 Gb USB stick can sometimes hold an entire company's vital data. Within minutes or even seconds an employee has all the files they need in order to start up their own business and take all the customers with them. Alternatively, what happens if a careless user accidentally compromises the network with an infected USB stick?

What does Microsoft have to say about it?
If you, the administrator, want to establish a minimum level of security, it is absolutely necessary to control which users can connect USB memory sticks to a computer. Unfortunately, a default Windows XP or Windows 2000 installation comes with no limitations on who is able to install and use USB storage media. Microsoft knowledge base article 823732 contains instructions on how to disable USB storage access for a certain group of users however, the article only distinguishes between whether or not a USB storage device has been installed on a particular computer. Furthermore, the instructions are limited to a stand-alone computer. According to the general rule of thumb "If it's tedious, there is a better way", I try to avoid techniques that force me to repeat certain tasks for each computer that I manage. That's what group policy objects (GPO) are for.