Multi-Signature Scheme Resistant to Randomness Injection Attacks - A Bitcoin Case
Łukasz Krzywiecki, Adam Polubek, Hannes Salin · 2021
We propose a modification of a multi-signature scheme, which was previously used as an enhancement of multi-signatures for the Bitcoin cryptocurrency. Our scheme is secure in a new stronger security model in which we allow the forger to inject or control the ephemeral (randomness) values in the end-user's signing device. Thus, our modified scheme is resistant to ephemeral key leakage attacks. We also provide a proof of concept implementation of our scheme, providing a time complexity and performance analysis.