Matthew Daniel Green (born 1976) is a cryptographer and security technologist. Green is an Associate Professor of Computer Science at the Johns Hopkins Information Security Institute. He specializes in applied cryptography, privacy-enhanced information storage systems, anonymous cryptocurrencies, elliptic curve crypto-systems, and satellite television piracy. He is a member of the teams that developed the Zerocoin anonymous cryptocurrency and Zerocash.. He has also been influential in the development of the Zcash system. He has been involved in the groups that exposed vulnerabilities in RSA BSAFE, Speedpass and E-ZPass.