A Group-Oriented Undeniable Signature Scheme for Unlikely Signers and Verifiers
Shin‐Jia Hwang, Hao-Chih Liao · Tamkang University Institutional Repository (TKUIR) · 2006
Lee and Hwang proposed group-oriented undeniable signature schemes with a trusted center to guard against Langford's attack. Unfortunately, there are some security weaknesses in Lee-Hwang's schemes. Their schemes assume that the signers and verifier should honestly perform steps; otherwise their schemes will fail. To remove this impractical assumption and the corresponding problems, our improvement is proposed.