Improved Impossible Differential Attacks against Round-Reduced LBlock

Abstract : Impossible differential attacks are among the most powerful forms of cryptanalysis against block ciphers. We present in this paper an in-depth complexity analysis of these attacks. We show an unified way to mount such attacks and provide generic formulas for estimating their time, data and memory complexities. LBlock is a well studied lightweight block cipher with respect to impossible differential attacks. While previous single-key cryptanalysis reached up to 22 rounds, by applying our method we are able to break 23 rounds with time complexity $2^{75.36}$ and data complexity $2^{59}$. Other time/data trade-offs are equally possible. This is to our knowledge the best (non-exhaustive search like) cryptanalysis of this function in the single-key model.
Document type :
Liste complète des métadonnées

Cited literature [23 references]  Display  Hide  Download
Contributor : Valentin Suder <>
Submitted on : Friday, September 26, 2014 - 2:40:20 PM
Last modification on : Saturday, October 27, 2018 - 1:20:04 AM
Document(s) archivé(s) le : Saturday, December 27, 2014 - 11:26:05 AM


Files produced by the author(s)


  • HAL Id : hal-01068887, version 1


Christina Boura, Marine Minier, María Naya-Plasencia, Valentin Suder. Improved Impossible Differential Attacks against Round-Reduced LBlock. [Research Report] 2014/279, IACR Cryptology ePrint Archive. 2014. 〈hal-01068887〉



Record views


Files downloads