The hacking group used a Tegra X1 flaw to modify code the Switch executes during its boot sequence.
With every new generation of gaming hardware, hackers set about trying to crack the software, take control of the system, and run their own programs. This typically begins with attempting to get a version of Linux running, and for the Nintendo Switch, it hasn’t taken very long to achieve.
The hacking group fail0verflow tweeted an image of Debian Linux running on a Switch. As TechCrunch reports, it seems Nintendo has hardware partner Nvidia to thank for this being possible.
— fail0verflow (@fail0verflow) February 6, 2018
The group first showed progress on hacking the Switch in January when they posted a scrolling demo running on Nintendo’s hybrid console. Later that month they confirmed it was possible due to a bootrom bug, which can’t be patched for any existing Switch hardware. That means Nintendo could only fix the bug (with Nvidia’s help) and apply it to newly made Switch consoles.
Running Linux also relies on the bootrom bug, which was discovered as a flaw in Nvidia’s Tegra X1 platform the Nintendo Switch uses. The bootrom executes code stored permanently on the Tegra X1 chip. Fail0verflow managed to bypass and replace the code somehow in order to run third-party software. Fixing it requires an update to the Tegra X1 chip, which is why Nintendo couldn’t fix the flaw for existing Switch hardware. It will be up to Nvidia to fix it going forward and then only if Nintendo asks them to. I would be surprised if Nintendo didn’t ask, though.
For now, fail0verflow is only sharing what they can do with their exploit, not how it works. If they do explain how to use it, the fact it doesn’t require any kind of hardware modification means we could get homebrew development happening on Switch. It would also be inevitable someone would figure out how to run pirate games.