Shih-Hung Kao and Tzonelih Hwang, “Comment on: Secure Quantum Dialogue Protocol Based on W States Without Information Leakage,” Cryptology and Information Security Conference 2014, May 30-31, National Cheng-Chi University, Taipei, Taiwan.
This study points out an information leakage problem in Zhou et al.’s quantum dialogue (QD) protocol [Int. J. Theor. Phys. DOI 10.1007/s10773-013-1615-2]. From the public information announced in the protocol, an external eavesdropper can obtain partial secret information without any active attack.