Forgeability of Wang-Zhu-Feng-Yau’s Attribute-Based Signature with Policy-and-Endorsement Mechanism

• 作 者: 葛爱军 黄欣沂 陈成 马传贵 张锐
• 机 构: State Key Laboratory of Mathematical Engineering and Advanced Computing, Zhengzhou Information Scien
• 出 处: Journal of Computer Science & Technology
• 发表日期: 2013年04期
• 关键词: signature signing proof secret signer attribute message valid satisfy assumption

Recently, Wang et al. presented a new construction of attribute-based signature with policy-and-endorsement mechanism. The existential unforgeability of their scheme was claimed to be based on the strong Diffe-Hellman assumption in the random oracle model. Unfortunately, by carefully revisiting the design and security proof of Wang et al.’s scheme, we show that their scheme cannot provide unforgeability, namely, a forger, whose attributes do not satisfy a given signing predicate, can also generate valid signatures. We also point out the flaws in Wang et al.’s proof.

Recently, Wang et al. Presented a new construction of attribute-based signature with policy-and-endorsement mechanism. The existential unforgeability of their scheme was claimed to be based on the strong Diffe-Hellman assumption in the random oracle model. Unfortunately, by carefully revisiting the design and security proof of Wang et al.’s scheme, we show that their scheme can not provide unforgeability, namely, a forger, whose attributes do not satisfy a given signing predicate, can also generate valid signatures. We also point out the flaws in Wang et al.’s proof.