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Keeping Secrets in Hardware: The Microsoft XboxTM Case Study

Part of the Lecture Notes in Computer Science book series (LNCS,volume 2523)


This paper discusses the hardware foundations of the cryptosystem employed by the XboxTM video game console from Microsoft. A secret boot block overlay is buried within a system ASIC. This secret boot block decrypts and verifies portions of an external FLASH-type ROM. The presence of the secret boot block is camouflaged by a decoy boot block in the external ROM. The code contained within the secret boot block is transferred to the CPU in the clear over a set of high-speed busses where it can be extracted using simple custom hardware. The paper concludes with recommendations for improving the Xbox security system. One lesson of this study is that the use of a high-performance bus alone is not a sufficient security measure, given the advent of inexpensive rapid prototyping services and affordable high-performance FPGAs.


  • Reset Signal
  • FPGA Board
  • Kernel Image
  • Symmetric Cipher
  • Video Game Console

These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© 2003 Springer-Verlag Berlin Heidelberg

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Huang, A. (2003). Keeping Secrets in Hardware: The Microsoft XboxTM Case Study. In: Kaliski, B.S., Koç, ç.K., Paar, C. (eds) Cryptographic Hardware and Embedded Systems - CHES 2002. CHES 2002. Lecture Notes in Computer Science, vol 2523. Springer, Berlin, Heidelberg.

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  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-00409-7

  • Online ISBN: 978-3-540-36400-9

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