密码学报（中英文）2025，Vol.12Issue(1)：84-95,12.DOI:10.13868/j.cnki.jcr.000750
对Aigis-Enc方案的密钥重用分析
Analysis of Key Reuse for Aigis-Enc Scheme
摘要
Abstract
The key recovery attack under plaintext checking is crucial for assessing the key reuse security of the algorithms.The Aigis-enc scheme,as a new type of post-quantum key encapsulation mechanism,currently lacks an evaluation of its key reuse security.For this reason,we analyze the key reuse security of the Aigis-enc scheme to help the scheme identify potential risks.The Aigis-enc scheme is derived from the public key encryption scheme Aigis-pke through the Fujisaki-Okamoto transformation.The key reuse security of the Aigis-enc scheme depends on the public key encryption scheme Aigis-pke.Specifically,we present a key recovery attack on the public key encryption scheme Aigis-pke under plaintext check in which the adversary determines whether the selected ciphertext can be decrypted into the given plaintext by querying the plaintext checking oracle,and then obtain the information about the secret key.After multiple queries,the adversary can fully recover the secret key.When evaluating the complexity of the attack,we give the actual number of queries required for the attack considering the probability distribution of the secret key.Finally,we give countermeasures to assure the secure application of the scheme in practice.关键词
后量子密码/格密码/密钥重用/主动攻击Key words
post quantum cryptography/lattice-based cryptography/key reuse/active attack分类
计算机与自动化引用本文复制引用
王克,宋非凡,李知行,张振峰,江浩东,谢惠琴..对Aigis-Enc方案的密钥重用分析[J].密码学报（中英文）,2025,12(1):84-95,12.基金项目
中央高校基本科研业务费(3282023002) （3282023002）
浙江省密码技术重点实验室开放课题(ZCL21009) （ZCL21009）
北京市自然科学基金(4234084)The Fundamental Research Funds for the Central Universities of China(3282023002) （4234084）
Open Research Fund of Key Laboratory of Cryptography of Zhejiang Province(ZCL21009) （ZCL21009）
Natural Science Foundation of Beijing Municipality(4234084) （4234084）
