Recently, Yan et al. proposed a quantum secure direct communication (QSDC) protocol with authentication using single photons and Einstein-Podolsky-Rosen (EPR) pairs (Yan et al., CMC-Computers, Materials \& Continua, 63(3), 2020). In this work, we show that the QSDC protocol is not secure against intercept-and-resend attack and impersonation attack. An eavesdropper can get the full secret message by applying these attacks. We propose a modification of this protocol, which defeats the above attacks along with all the familiar attacks.

中文翻译：

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基于单光子和贝尔态相互认证的量子安全直接通信协议密码分析

最近，严等人。提出了一种使用单光子和爱因斯坦-波多尔斯基-罗森 (EPR) 对进行身份验证的量子安全直接通信 (QSDC) 协议（Yan 等人，CMC-Computers, Materials \& Continua, 63(3), 2020）。在这项工作中，我们表明 QSDC 协议对于拦截和重发攻击和模拟攻击是不安全的。窃听者可以通过应用这些攻击来获取完整的秘密消息。我们建议对该协议进行修改，以击败上述攻击以及所有熟悉的攻击。