As a candidate of the standard of post-quantum cryptography for NIST,Liu,et al.submitted a new public-key encryption scheme Compact-LWE,whose structure is similar to LWE,but with different distribution of errors.They ...As a candidate of the standard of post-quantum cryptography for NIST,Liu,et al.submitted a new public-key encryption scheme Compact-LWE,whose structure is similar to LWE,but with different distribution of errors.They thought that the special error distribution would protect Compact-LWE from known lattice-based attacks.Furthermore,they recommended a set of small parameters to improve the efficiency of Compact-LWE and claimed it can offer 192-bit security.However,in this paper,the authors show that Compact-LWE is not secure under recommended parameters by presenting two ciphertext-only attacks.First,the authors show that the message can be recovered efficiently from the ciphertext.Then the authors go further to recover an equivalent private key efficiently from the public key by exploiting the special structure of Compact-LWE.展开更多
基金supported by the National Natural Science Foundation of China under Grant No.61572490the National Key Research and Development Project under Grant No.2018YFA0704705the National Center for Mathematics and Interdisciplinary Sciences,CAS。
文摘As a candidate of the standard of post-quantum cryptography for NIST,Liu,et al.submitted a new public-key encryption scheme Compact-LWE,whose structure is similar to LWE,but with different distribution of errors.They thought that the special error distribution would protect Compact-LWE from known lattice-based attacks.Furthermore,they recommended a set of small parameters to improve the efficiency of Compact-LWE and claimed it can offer 192-bit security.However,in this paper,the authors show that Compact-LWE is not secure under recommended parameters by presenting two ciphertext-only attacks.First,the authors show that the message can be recovered efficiently from the ciphertext.Then the authors go further to recover an equivalent private key efficiently from the public key by exploiting the special structure of Compact-LWE.
