A Known Plaintext Attack of FEAL-4 and FEAL-6

  • Anne Tardy-Corfdir
  • Henri Gilbert
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 576)


We present new results on the cryptanalysis of the FEAL-N blockcipher. As a matter of fact, almost all the attacks of this cryptosystem published so far are chosen plaintext attacks [3,4,5,7], except the announcement in [7] of a non-differential known plaintext attack of FEAL-4 which requires about 100000 plaintext blocks. We describe known plaintext attacks of FEAL-4 and FEAL-6, which require about 1000 and 20000 plaintext blocks respectively and are based on correlations with linear functions. Using similar methods, we have also found more recently an improved attack on FEAL-4, which requires only 200 knwon plaintext blocks.


Plaintext Attack Choose Plaintext Attack Intermediate Block Plaintext Block Feistel Scheme 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1992

Authors and Affiliations

  • Anne Tardy-Corfdir
    • 1
  • Henri Gilbert
    • 1
  1. 1.Centre National d’Etudes des Télécommunications (CNET)PAA/TSA/SRCIssy les MoulineauxFrance

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