云环境中支持隐私保护的可计算加密方法的CCA攻击

CCA Attack on Privacy Preserving Computable Encryption Scheme of Cloud Computing

为保护用户隐私和提供用户有效服务,在云计算服务中通常将用户外包数据以密文形式保存,并使用隐私保护加密方案处理密文数据.研究分析云计算服务中外包数据的隐私保护加密方案安全性非常重要.针对基于矩阵和向量运算设计的可计算加密方案(CESVMC),本文通过明密文对求解加密方案等价私钥的方法证明CESVMC加密方案不是IND-CCA安全的.

To protect users＇ privacy and present efficient services for users, the encrypted outsourcing data are generally stored and processed in cloud computing by applying privacy preserving encryption schemes. It is very important to analyze the security of the privacy preserving encryption scheme for the outsourcing data in cloud computing. For a computable encryption scheme based on vector and matrix calculation （ CESVMC ）, this paper shows that CESVMC is not IND-CCA secure by solving an equivalent secret key from some plaintext-ciphertext pairs of CESVMC.