The Bitfinex hack was due to getting enough parties of the multiparty signature to sign it (e.g. by stealing 2 out of 3 keys, or taking advantage of insufficien

The Bitfinex hack was due to getting enough parties of the multiparty signature to sign it (e.g. by stealing 2 out of 3 keys, or taking advantage of insufficiently secure automatic signing systems), not an issue with the contract itself.