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arXiv · 1105.1232

On the "Security analysis and improvements of arbitrated quantum signature schemes"

Song-Kong Chong·Yi-Ping Luo·Tzonelih Hwang
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Abstract

Recently, Zou et al. [Phys. Rev. A 82, 042325 (2010)] pointed out that two arbitrated quantum signature (AQS) schemes are not secure, because an arbitrator cannot arbitrate the dispute between two users when a receiver repudiates the integrity of a signature. By using a public board, they try to propose two AQS schemes to solve the problem. This work shows that the same security problem may exist in their schemes and also a malicious party can reveal the other party's secret key without being detected by using the Trojan-horse attacks. Accordingly, two basic properties of a quantum signature, i.e. unforgeability and undeniability, may not be satisfied in their scheme.

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Song-Kong Chong, Yi-Ping Luo, Tzonelih Hwang. 2011-05-06. On the "Security analysis and improvements of arbitrated quantum signature schemes". https://doi.org/10.1103/physreva.85.056301

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