Securing Multi-party Crypto Wallets

Abstract

Threshold Signature Scheme (TSS) is part of the Multi-Party Computation (MPC) problem, which enables multiple parties to generate digital signatures without revealing any secret information. Avoiding a single point of failure (SPOF) is essential in any financial system; therefore, cryptocurrencies which use digital signatures need a mechanism similar to TSS to eliminate the SPOF, the private key of the crypto wallet. Despite the advantages of TSS, many bugs related to its implementations have been reported. In this study, we will propose security solutions based on Trusted Execution Environment (TEE) for key generation and signing phases in multi-party crypto wallets. We leverage TEE to bind a verifiable identity to each TSS party allowing them to authenticate honest players and prevent malicious actors from joining the protocol. The evaluation results show that the proposed solution meets the security requirements of multi-party crypto wallets and can be deployed in the production environment.