This is impressive, especially given how cheaply the attack can be realized. If you can get near the device you only need a coil and a sound card.
That being said:
> After observing the elliptic-curve double and add operations during a few thousand signatures, the secret signing key can be completely reconstructed.
This is probably the biggest obstacle for pulling this off in reality. I have no idea what that means in minutes or hours you have to be near a phone doing encryption though.
That being said:
> After observing the elliptic-curve double and add operations during a few thousand signatures, the secret signing key can be completely reconstructed.
This is probably the biggest obstacle for pulling this off in reality. I have no idea what that means in minutes or hours you have to be near a phone doing encryption though.