Many zero-knowledge proof projects are threatened by attacks like faking proof, double spending and replaying due to the ‘Input Aliasing’ bug caused by a contract library of zkSNARKs. This applies to many Ethereum open-source projects as well, including 3 most popular zkSNARKs library - snarkjs, ethsnarks, ZoKrates and 3 topical mixcoin apps - hopper, Heiswap, Miximus.