The Windows debugging facility provides a means for programs to perform diagnostic and analytic functions on applications as they are running on the operating system. One of these capabilities allows for a program, usually a debugger, to connect to any running program, and to take control of it. The program can then issue commands to the controlled program, including the ability to start other programs. These commands would then execute in the same security context as the controlled program.

There is a flaw in the authentication mechanism for the debugging facility such that an unauthorized program can gain access to the debugger. A vulnerability results because an attacker can use this to cause a running program to run a program of her choice. Because many programs run as the operating system, this means that an attacker can exploit this vulnerability to run code as the operating system itself. She could take any action on the system including deleting data, adding accounts with administrative access, or reconfiguring the system.