Mistakes Microsoft Made in the Xbox Security System

The Xbox is a gaming console, which has been introduced by Microsoft Corporation in late 2001 and competed with the Sony Playstation 2 and the Nintendo GameCube. Microsoft wanted to prevent the Xbox from being used with copied games, unofficial applications and alternative operating systems , and therefore designed and implemented a security system for this purpose. This article is about the security system of the Xbox and the mistakes Microsoft made. It will not explain basic concepts like buffer exploits, and it will not explain how to construct an effective security system, but it will explain how not to do it: This article is about how easy it is to make terrible mistakes and how easily people seem to overestimate their skills. So this article is also about how to avoid the most common mistakes. For every security concept, this article will first explain the design from Microsoft's perspective, and then describe the hackers' efforts to break the security. If the reader finds the mistakes in the design, this proves that Microsoft has weak developers. If, on the other hand, the reader doesn't find the mistakes , this proves that constructing a security system is indeed hard. Because Microsoft had a very tight time frame for the development of the Xbox, they used off-the-shelf PC hardware and their Windows and DirectX technologies as the basis of the console. The Xbox consists of a Pentium III Celeron mobile 733 MHz CPU, 64 MB of RAM, a GeForce 3 MX with TV out, a 10 GB IDE hard disk, an IDE DVD drive, Fast Ethernet, as well as USB for the gamepads. It runs a simplified Windows 2000 kernel, and the games include adapted versions of Win32, libc and DirectX statically linked to them. Although this sounds a lot more like a PC than, for example, a GameCube with its PowerPC processor, custom optical drive and custom gamepad connec-tors, it is important to point out that, from a hardware point of view, the Xbox shares all properties of a PC: It has LPC, PCI and AGP busses, it has IDE drives, it has a Northbridge and a Southbridge, and it includes all the legacy PC features such as the " PIC " interrupt controller, the " PIT " timer and the A20 gate. nVidia sold a slightly modified South-bridge and a Northbridge with a another graphics core embedded for the PC …