Breaking the Ledger Security Model

[bitwelder]

https://saleemrashid.com/2018/03/20/breaking-ledger-security-model/

Not much impressed by the general behaviour of the Ledger team

[thm_w]

Good write up.
The guy is apparently 15 years old as well, if they were smart they would offer him a job.

[bitwelder]

By the way, the young guy took already the other h/w wallet for a spin 
https://saleemrashid.com/2017/08/17/extracting-trezor-secrets-sram/

[mikeselectricstuff]

So if the magic security chip is a peripheral, and the MCU controls the USB and OLED, why couldn't malicious firmware just ignore the security chip altogether, and implement fake security functionality internally?
Am I missing something ?

[thm_w]

So if the magic security chip is a peripheral, and the MCU controls the USB and OLED, why couldn't malicious firmware just ignore the security chip altogether, and implement fake security functionality internally?
Am I missing something ?

If you do this after the user has setup their account, etc. then you would not have access to the private keys on the secure chip (SE).

If you do this before initialization, and feed the user a false seed or similar, that would be an option. But then I assume it would not authenticate via their web application. There must be some Ledger private keys in the SE as well that allow firmware updates and SE verification.

https://support.ledgerwallet.com/hc/en-us/articles/115005321449-How-to-verify-the-security-integrity-of-my-Nano-S-

4) The root of trust for the current batch is the following secp256k1 public key : 0490f5c9d15a0134bb019d2afd0bf297149738459706e7ac5be4abc350a1f818057224fce12ec9a65de18ec34d6e8c24db927835ea1692b14c32e9836a75dad609 - as checked here Genuine.py

[Marco]

This is why I trust open source tokens you can just program yourself more (of course physical access is an instant loss). It would be nice to have open source and tamper proof chips, but if I have to chose I prefer open source when doing business with this kind of company with so little skin in the game.

It's different for my bank, then again if some hack happens against the hardware I got from my bank they'll generally just refund any money lost ... just like they did for skimming. I have more cause to trust them.