[tinganho]

I actually did a bit of research on this before.

For easier chips like TPMs(Trusted Platform Module). What I've seen people do when trying to steal secrets(key) on a chip is to buy multiples of the same chip. On each chip expose the layer under a microscope(A chip exist of multiple layers, thats why we need multiple chips). Now, you know everything to reverse engineer the secrets. There exists tools for drilling and probing each trace on the chip. Here is an example. https://www.youtube.com/watch?v=h-hohCfo4LA

I think what you mean by charging a huge capacitor and blowing up the secrets. You refer to an HSM(Hardware Security Module). They typically have sensors to detect any fraudulent behavior. They are much harder hack. But there is always holes in each HSM. I think hackers use the same technic there as well. Buy multiple HSM to figure out the design. Reverse engineer the traces and try to probe without being detected on the target device. To my knowledge there are currently no sensors that are 100% bullet proof. They can either be fooled or have weak spots.

[teddyh]

> On each chip expose the layer under a microscope

Or use X-ray tomography:

https://news.ycombinator.com/item?id=13952016

[baybal2]

Gemalto at least had that flaw - it had a lot of circuits to detect probing, but a circuit that feeds fuse blower is easy to disconnect/damage even under optical microscope

[ggm]

Thats reading the chip. How about mending a blown fuse?