We present a cryptanalysis of a signature scheme HIMQ-3 due to Kyung-Ah Shim et al [10], which is a submission to National Institute of Standards and Technology (NIST) standardization process of post-quantum cryptosystems in 2017. We will show that inherent to the signing process is a leakage of information of the private key. Using this information one can forge a signature.

中文翻译：

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多元签名方案HIMQ-3的奇异攻击

由于Kyung-Ah Shim等人，我们对签名方案HIMQ-3进行了密码分析[10]，这是提交给美国国家标准技术研究院（NIST）在2017年发布的后量子密码系统的标准化流程。我们将证明签名流程的内在本质是私钥信息的泄漏。使用此信息，可以伪造签名。