Concurrently-Secure Blind Signatures Without Random Oracles or Setup Assumptions

Abstract. We show a new protocol for blind signatures in which security is preserved even under arbitrarily-many concurrent executions. The protocol can be based on standard cryptographic assumptions and is the first to be proven secure in a concurrent setting (under any assumptions) without random oracles or a trusted setup assumption such as a common reference string. Along the way, we also introduce new definitions of security for blind signature schemes.

• Type: Conference
• Year: 2007
• Where: TCC
• Authors: Carmit Hazay, Jonathan Katz, Chiu-Yuen Koo, Yehuda Lindell
• Keywords: Arbitrarily-many Concurrent Executions, Blind Signature, Cryptography, Standard Cryptographic Assumptions, TCC 2007