Hardware Tutorial

Xbox One Elite 2 Controller and Hardware Measurements

Xbox One "Bliss Hack" Open-Source Modchip in Development by GFL_Tech

RainReach · 2026-06-10T21:48:05+00:00

Hey everyone, As many of you saw at the RE//verse conference, researcher Markus "doom" Gaasedelen blew the Xbox One’s security wide open with the "Bliss" exploit—a hardware-level Voltage Glitch Hack (VGH) targeting the secure boot ROM. Because this attack exploits physical silicon behavior during early boot, it is completely unpatchable. While Mark proved the concept, we haven't had a consumer-ready "modchip" to automate this process for regular users. However, hardware developer GFL_Tech has officially stepped up to change that. They have launched an open-source hardware project to design, build, and code a functional physical modchip for the Bliss Hack. I wanted to put together a tracking thread here on GBATemp to log their engineering progress, layout the roadmap, and get more eyes from the HW hacking scene on this project. The Hardware and How It Works Unlike the original Xbox ModXO project, which uses a cheap Raspberry Pi RP2040 to mimic a flash chip, glitching the Xbox One requires insane, sub-nanosecond timing precision. The GFL_Tech modchip is currently leveraging a hybrid approach to tackle the security processor: Signal Processing: Utilizing a TLV3201 high-speed comparator circuit to clean up and track the motherboard's hardware states. Sidechannel Isolation: Designing a custom Quick Solder Board (QSB) to hook directly into the EFUSE lines, tuning resistor values to kill signal noise. The Glitch Trigger: The end goal is using a microcontroller/CPLD setup to automatically sweep timing profiles against the EMMC DAT0 lines to intercept execution flow and drop the voltage rail at the exact microsecond required. The Project Roadmap and Current Status GFL_Tech is treating this as a transparent, step-by-step engineering journey. Here is where the project currently sits: Phase 1: Sourcing and teardown of a 2013 "Day One" Xbox One retail testbed. (Completed) Phase 2: Successful testing of the TLV3201 comparator circuit. (Completed) Phase 3: Finalizing the EFUSE QSB layout and stabilizing pull-up/pull-down noise. (In Progress) Phase 4: Coding the automated glitch-sweep logic for the MCU. (Planned) Phase 5: Real-time timing sweeps against the EMMC lines to hijack execution flow. (Planned) Phase 6: Public V1 Release featuring open-source PCB schematics, code, and installation guides for the community to test and refine. (Planned) Where to Follow and Contribute If you want to look at the hardware schematics, trace their engineering steps, or contribute to the codebase, everything is being kept open: GitHub Source: https://github.com/GFLTech/Xbox-One-Bliss-Hack-GFL_Tech-Modchip- to check out the wiki and hardware roadmaps. Video Devlogs: They are documenting the actual hardware breakdowns, scope readouts, and circuit testing on YouTube under the handle @GFL_Tech. Videos

Hello, Xbox One community. I am a crazy person from the DS Forum who measured all of the screws and hardware from the DS and 3DS family of consoles. I have been branching out recently to other consoles, and so, a busted Elite 2 controller ended up on my desk. Also, congratulations on the discovery of the system glitching method. I am very excited to see what develops from that.

I felt I should measure the screws. Since the time that I measured the screws for the DS and 3DS, I have gotten calipers and a better understanding of screwdrivers, so I hope to deliver a fairly accurate base of measurements to work with. I do intend on going back to those posts to update them, but.... time.

I'll simplify these posts so they aren't as unwieldy as my other posts.

How I Measure Screws.

Using a custom chart that I made, I will be using this as a reference to measure each screw with my calipers.

Measurements done with Calipers will only be done on one screw per category, and will be subject to some amount of inaccuracies due to the size of the screws and the tools I have. Measurements like Thread Pitch, Shank Length, Thread Length, and Recess Width are done by eyeballing it with my calipers and a microscope. Measurements like Thread Diameter and Screw Length will be far more accurate as I can physically clamp them in my calipers.

Resources and Set Up.

Screws will be sorted by size, going from shortest to longest, rounded to the nearest 0.5mm. In the cases where screws weren't rounded to the whole or half steps, I found their measurements consistent with other screws of the same category; thus, they were labeled with their non-standard measurement.

I'll add links to an IFixIt Guide to match my terms to pictures (i.e., Motherboard Screw would point to the Motherboard removal step of an IFixIt guide). If there is no guide, I won't be able to link.

The IFixIt guide I will be referring to for the majority of this post is the Battery Replacement Guide, but I will be referencing other guides. From what I see, iFixit doesn't cover the removal of the paddle buttons, so I will be unable to link to a guide for those.