The lightweight block cipher PRIDE designed by Albrecht et al., appears in CRYPTO 2014. The designers claim that their method of constructing linear layer is good both in security and efficiency. In this paper, we find 16 different 2-round iterative characteristics utilizing the weaknesses of S-box and linear layer, construct several 15-round differentials. Based on one of the differentials, we...

Khudra is a 18-round lightweight block cipher proposed by Souvik Kolay and Debdeep Mukhopadhyay in the SPACE 2014 conference which is applicable to Field Programmable Gate Arrays (FPGAs). In this paper, we obtain 2 14-round related-key impossible differentials of Khudra, and based on these related-key impossible differentials for 32 related keys, we launch an attack on the full Khudra with data...

GOST block cipher designed in the 1970s and published in 1989 as the Soviet and Russian standard GOST 28147-89. In order to enhance the security of GOST block cipher after proposing various attacks on it, designers published a modified version of GOST, namely GOST2, in 2015 which has a new key schedule and explicit choice for S-boxes. In this paper, by using three exactly identical portions of ...

A growing number of connected objects, with their high performance and low-resources constraints, are embedding lightweight ciphers for protecting the confidentiality of the data they manipulate or store. Since those objects are easily accessible, they are prone to a whole range of physical attacks, one of which are fault attacks against for which countermeasures are usually expensive to implem...

Algebraic analysis of block ciphers aims at finding the secret key by solving a collection of polynomial equations that describe the internal structure of a cipher for chosen observations of plaintext/ciphertext pairs. Although algebraic attacks are addressed for cryptanalysis of block and stream ciphers, there is a lack of understanding of the impact of algebraic representation of the cipher o...

In this paper we present a rather new approach to apply mixed-integer optimization to the cryptanalysis of cryptographic primitives. We focus on the stream cipher Trivium, that has been recommended by the eSTREAM stream cipher project, and the lightweight block cipher Ktantan. Using these examples we explain how the problem of solving a non-linear multivariate Boolean equation system can be for...

Simon and Speck are two families of ultra-lightweight block ciphers which were announced by the U.S. National Security Agency in June 2013. Yet, the specification discusses only the design and the performance of both cipher families and the task of analyzing their security has been left to the were proposed by the U.S. National Security Agency in June 2013. Yet, the specification paper discusse...

In this paper, a privacy preserving authentication protocol for RFID that relies on a single cryptographic component, a lightweight stream cipher, is constructed. The goal is to provide a more realistic balance between forward privacy and security, resistance against denial of service attacks, and computational efficiency (in tags and readers) than existing protocols. We achieve this goal by so...

In the present era of e-world where security has got a larger weightage, cryptography has its role to play. Nowadays, the devices available in the market are of resource constrained type. Hence we need lightweight ciphers for the efficient encryption of data thereby increasing the performance. In this project a detailed study of HIGHT cryptographic algorithm is done which outperforms standard a...

Most of the lightweight block ciphers are nibble-oriented as the implementation of a 4-bit S-box is much more compact than an 8-bit S-box. This paper proposes a novel implementation of multiplicative inverse for 8-bit S-boxes using LFSR requiring only 138 gate-equivalent. It can be shown that if such S-boxes are adopted for the AES it takes less than 50 gate-equivalent per S-box in parallel imp...