Photon-Emission-Guided Laser Fault Injection Enables RP2350 Secure Debug

stackghost

> The attack requires physical access, destructive preparation, and approximately $250,000 of laboratory equipment. Not super practical, but neat attack

Fred27

There's always an XKCD... https://xkcd.com/538/

jacquesm

That's reminiscent of when we first found out that if you opened up dram chips you could use them for imaging. Of course the scale at which this is done is extremely impressive.

brcmthrowaway

Now it can be done for Apple iPhone. Apple is cooked.

BitBangingBytes

I appreciate all the details they provide in the post. The $250k in lab gear is useful when initially discovering, exploiting and documenting attacks like this. Definitely doable in a home lab for under $25k in equipment, likely under $10k. Same as my replicating Colin O’Flynn’s BAM BAM attack on a MPC5566 chip, he used a ChipShouter ($5,000) and I used a PicoEMP ($50). https://youtu.be/URmI1VVilek

byb

The RP2350's secure enclave made it particularly attractive for use as a Yubikey alternative. There will always be an arms race between safe-crackers and safe-builders. Presumably the lessons learned will help make the next generation tougher to break into.

akoboldfrying

Impressive work! I have a side question. I looked into the linked Raspberry Pi hacking challenge, and there's something very basic I couldn't figure out: It looks like the relevant script in the repo just writes 0xc0ff 0xffee a few times to the OTP as the "secret" to unlock. But given that $20000 was up for grabs, this can't possibly be the genuine secret being sought to claim the prize. (Indeed, I can't think of a secure way to install a secret from a public GitHub repo unless it involves running on-device code that encrypts something using some other , factory-installed secret key, which is just kicking the can down the road.) And given that the OTP on a brand new RP23550 is initialised to all zeros, it can't be that the genuine secret is programmed in at the factory either. What am I missing? How does the genuine secret get installed on a person's RP2350?

rkagerer

The RP2350 is Raspberry Pi’s dual-core microcontroller: each processor socket can select either an Arm Cortex-M33 or a RISC-V Hazard3 core at boot. Does that mean there are four cores on the die? Is there crazy amounts of MUXing going on? Does the extra, semi-unused area give the chip a premium price tag? Or did I misinterpret this?