Dealer-Leakage Resilient Verifiable Secret Sharing

Verifiable Secret Sharing (VSS) guarantees that honest parties reconstruct a consistent secret even in the presence of a malicious dealer that distributes invalid shares. We empower the dishonest dealer and consider the case when he subliminally leaks information in valid shares, allowing an adversary to access the secret prior to the reconstruction phase. We define the concept of Dealer-Leakage Resilient Verifiable Secret Sharing (DLR-VSS) as a stronger notion of VSS that achieves security under this settings. We propose an efficient DLR-VSS and prove its properties in the semi-honest adversarial model.