## Cryptology ePrint Archive: Report 2014/978

Improved Differential Analysis of Block Cipher PRIDE

Qianqian Yang and Lei Hu and Siwei Sun and Kexin Qiao and Ling Song and Jinyong Shan and Xiaoshuang Ma

Abstract: In CRYPTO 2014 Albrecht \emph{et al.} brought in a 20-round iterative lightweight block cipher PRIDE which is based on a good linear layer for achieving a tradeoff between security and efficiency. A recent analysis is presented by Zhao \emph{et al.}. Inspired by their work, we use an automatic search method to find out 56 iterative differential characteristics of PRIDE, containing 24 1-round iterative characteristics, based on three of them we construct a 15-round differential and perform a differential attack on the 19-round PRIDE, with data, time and memory complexity of $2^{62}$, $2^{63}$ and $2^{71}$ respectively.

Category / Keywords: secret-key cryptography / Block Cipher, PRIDE, Differential attack, Active S-box, Automatic Method