$ cd /projects/xbox-hacking
2026-02-28

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Hacking the Original Xbox

GitHub: lost to a TrueCrypt boot sector wipe


PRE — Idea · Setup · Build

Late 2001. The Xbox launched in North America. I imported one
from Canada to Germany before the European release because
waiting was not an option. Plugged it into a projector. Played
HALO all night. It was glorious.

Then I got curious about what was inside.

I got access to Microsoft's official Xbox Development Kit —
the XDK. And those early revisions? Microsoft had shipped PDB
debug symbols with their development kernels. The kernels
themselves were basically x86 executables. Which meant you
could load them into IDA Pro and read them like a book.

So I did.

I was 26 years old, armed with a disassembler, and I started
pulling apart Microsoft's security architecture thread by
thread.

The Group

There were maybe five of us. Distributed worldwide.
Communicating through encrypted IRC channels. Each approaching
the Xbox security scheme from a different angle. Hardware
probing, software reversing, firmware analysis.

My angle was the software. The debug kernels. The XDK. IDA Pro
running for days while I traced execution paths through
Microsoft's protection layers.

This was never about piracy. It was about the puzzle. Microsoft
had built what they believed was an unbreakable security system
for a consumer device. We wanted to know if that was true.

The Discovery

Deep in the disassembly of the development kernels, I found
it: the retail Xbox kernel was encrypted with RC4 — a
symmetric stream cipher using a 128-bit key. The debug kernels
referenced the mechanism, but the actual decryption key wasn't
in the software. It had to come from somewhere on the hardware
— a hidden EEPROM that the bootloader read on startup.

RC4 with a 128-bit key. Symmetric encryption. That meant one
key to encrypt, the same key to decrypt. Find the key, and the
entire retail kernel opens up. Every game disc verification
routine, every security check, every protection mechanism —
all readable.

One of the people in our group was Andrew "Bunnie" Huang, an
MIT researcher who was approaching the Xbox from the hardware
side. I told him what I'd found in the software: look for a
128-bit RC4 key, sitting in some hidden EEPROM on the
motherboard. Try to RC4-decrypt the retail kernel binary with
whatever you find. Once it decrypts cleanly, you've got the
right key.

Bunnie went after it from the hardware side. He tapped the
HyperTransport bus between the Southbridge and the CPU. He
found the secret boot code. He found the key. He decrypted
the retail kernel.

As he described in his book and his MIT paper: the RC4 key was
stored at a specific address inside the hidden MCPX boot ROM,
and it traversed the bus in the clear on every boot. Once
captured, the entire security scheme unraveled.

That discovery triggered a cascade.

The Cascade

The 16-byte key was shared in an IRC channel. We asked for it
to be deleted immediately. It was too late. Multiple groups had
already seen it. Within weeks, the first generation of modchips
appeared on the market. The Xbox security scheme was broken.

Once the retail kernel could be decrypted, everything became
possible. Custom firmware. Homebrew software. Media center
applications. And yes — piracy. The same key that enabled
legitimate tinkering also enabled illegitimate copying. That's
the dual-use nature of any security research, and it's a
tension that never resolves cleanly.

The Builder

After the initial breakthrough, I went deeper. As the
community's understanding of the Xbox kernel grew, I rebuilt
the C++ build chain and got it working. From there, I could
compile custom kernels and extend them with new features.

I built custom BIOS software for the Xbox homebrew scene.
System menus, configuration tools, hardware diagnostics, video
mode utilities, quality-of-life features for the growing
community of people running modified consoles. Navigate menus
with the controller, launch applications from the hard drive,
customize boot animations.

A full custom operating environment for a game console. I was
27, writing operating system code and shipping it to a global
community.

Some of that code is still running today. The Xbox retro scene
on YouTube features setups booting into BIOS software I wrote
over two decades ago. The green menu screens, the configuration
options, the quick-launch features — that's my work, still
alive in a subculture I haven't been part of in twenty years.

The Fear

Then Microsoft started hunting.

People in the scene were arrested. People I knew. The legal
hammer came down hard on anyone connected to circumvention
devices. The DMCA in the US, equivalent laws in Europe —
this wasn't theoretical liability. People went to prison.

I was terrified. I was a young programmer in Germany who had
spent months deep inside Microsoft's proprietary security
architecture. The paranoia was constant. Every unexpected
knock on the door. Every unfamiliar car parked outside.

I had been operating under a handle — "headache" — and I
had been careful about separation between my real identity and
my scene identity. But careful isn't the same as safe. I even
asked Bunnie to obfuscate my handle in the book — "head"
instead of "headache." Every layer of distance felt necessary.

Eventually, I stepped back. The scene moved on. New Xbox
revisions came out with updated security. The original Xbox
faded from the spotlight, and with it, so did I.

The original Xbox has been off the market for two decades. The
legal landscape for that era of console security research has
since been extensively documented, litigated, and closed.

The Ironic End

All my tools, scripts, custom builds, IDA Pro databases,
kernel modifications, build chain configurations — everything
I'd created over two years of intense work — lived on a
single hard drive encrypted with TrueCrypt full-disk
encryption.

One day I accidentally erased the boot sector.

Everything. Gone. In a second. The guy who broke Microsoft's
encryption destroyed his own life's work with his own
encryption. No backup. No recovery. Just silence.

The only proof that any of it existed is a credit in a book.

POST — Learnings · Afterthoughts · Timeline

What happened:

I helped crack the security of a major consumer electronics
device at 26. I discovered the cryptographic architecture that
protected it. I pointed a hardware researcher toward the
physical location of the decryption key. I built custom
operating system software that ran on millions of modified
consoles worldwide. And then I lost all evidence of it to my
own encryption.

Learnings:
  - Security through obscurity doesn't work. Microsoft built
    their entire Xbox protection on the assumption that nobody
    would look inside. Five people with IRC and curiosity
    proved that wrong in months.
  - RC4 is a symmetric cipher. One key for everything. That's
    a single point of failure for an entire platform. Microsoft
    learned this lesson — the Xbox 360 used a fundamentally
    different security architecture.
  - The line between security research and criminal liability
    is drawn by lawyers, not engineers. The same knowledge that
    enables understanding enables exploitation. That tension is
    real and permanent.
  - Back up your encrypted drives. Or at least back up the
    headers.
  - The most intense learning experiences of my life happened
    outside of any institution. No university taught me x86
    reverse engineering, kernel internals, or cryptographic
    analysis of real-world systems. A disassembler and an
    obsession did.

The book:
  Andrew "Bunnie" Huang published "Hacking the Xbox: An
  Introduction to Reverse Engineering" in 2003, supported
  by the Electronic Frontier Foundation. It documents the
  technical process of breaking the Xbox security scheme
  and became a foundational text in hardware security
  research. I am credited under my handle "head" in the
  acknowledgments.

  Bunnie went on to become one of the most respected
  hardware hackers in the world. His work on open hardware,
  including the Novena open-source laptop and the NeTV
  video adapter, built on the same principles we explored
  together on the Xbox: if you own the hardware, you should
  be allowed to understand it.

Timeline:
  - 2001: Imported Xbox from Canada. HALO on a projector.
  - 2002: Obtained XDK. Started reversing debug kernels in
    IDA Pro. Discovered RC4 encryption scheme. Pointed Bunnie
    Huang toward the hardware key. Key discovered and leaked.
    First generation modchips appear.
  - 2002-2004: Built custom BIOS software and system tools
    for the Xbox homebrew scene. Compiled custom kernels from
    source. Shipped to a global community.
  - 2003: "Hacking the Xbox" published by Bunnie Huang.
    Credited as "head" in the acknowledgments.
  - ~2004: Scene faded as new Xbox revisions changed the
    security landscape. Stepped back.
  - Date unknown: TrueCrypt boot sector accident. All tools,
    scripts, and builds permanently lost.

Status: Closed. The code is gone. The book remains. The retro
  scene keeps the software alive without knowing who wrote it.
  And somewhere in a drawer, there's a first edition of
  "Hacking the Xbox" with my name in it.

  I didn't talk about any of this for over twenty years.
  This page is the first time.