Created a voltage drop that exactly occurred to be timed to the key comparison, then a spike at the continuation.

Irl noop and forced execution control flow to effectively return true.

B e a utiful

It's fascinating - how does one defend against an attacker or red-team who controls the CPU voltage rails with enough precision to bypass any instruction one writes? It's an entirely new class of vulnerability, as far as I can tell.

This talk https://www.youtube.com/watch?v=BBXKhrHi2eY indicates that others have had success doing this on Intel microcode as well - only in the past few months. Going to be some really exciting exploits coming out here!

> how does one defend against an attacker or red-team who controls the CPU voltage rails

The xbox does have defences against this, the talk explicitly mentions rail monitoring defences intended to detect that kind of attack. It had a lot of them, and he had to build around them. The exploit succeeds because he found two glitch points that bypassed the timing randomisation and containment model.