Fireblocks is one of the leading cryptocurrency wallets which distributes trust between the application provider and the client in order to mitigate central points of attack. As opposed to storing the private key in a single location, Fireblocks never materializes it and instead shards the secret among Fireblocks servers and the client’s mobile devices. To sign a blockchain transaction, a quorum of at least 3 endpoints conduct an MPC signature protocol to generate a valid signature on a proposed user transaction. In addition, Fireblocks stores keys and API keys in SGX so they cannot be extracted even if malware or a hacker has control over the server’s OS.
Links
White Paper: Fireblocks’ Multi-layer Philosophy for Securing Digital Assets