Improved Impossible Differential Cryptanalysis of 7-Round AES-128

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6498)


Using a new 4-round impossible differential in AES that allows us to exploit the redundancy in the key schedule of AES-128 in a way more effective than previous work, we present a new impossible differential attack on 7 rounds of this block cipher. By this attack, 7-round AES-128 is breakable with a data complexity of about 2106 chosen plaintexts and a time complexity equivalent to about 2110 encryptions. This result is better than any previously known attack on AES-128 in the single-key scenario.


AES block cipher cryptanalysis impossible differential 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  1. 1.Cryptography & System Security Research Laboratory, Department of Electrical and Computer EngineeringIsfahan University of TechnologyIsfahanIran
  2. 2.COSIC, Dept. of EEKULeuven and IBBTHeverleeBelgium
  3. 3.IAIKGraz University of TechnologyGrazAustria

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