Cryptanalysis of the Stream Cipher ABC v2

  • Hongjun Wu
  • Bart Preneel
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4356)


ABC v2 is a software-efficient stream cipher with 128-bit key. In this paper, we apply a fast correlation attack to break ABC v2 with weak keys. There are about 296 weak keys in ABC v2. The complexity to identify a weak key and to recover the internal state of a weak key is low: identifying one weak key from about 232 random keys requires 6460 keystream bytes and 213.5 operations for each random key. Recovering the internal state of a weak key requires about 219.5 keystream bytes and 232.8 operations. A similar attack can be applied to break ABC v1 with much lower complexity than the previous attack on ABC v1.


Fast correlation attack key-dependent S-box stream cipher ABC v2 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Hongjun Wu
    • 1
  • Bart Preneel
    • 1
  1. 1.Katholieke Universiteit Leuven, ESAT/SCD-COSIC, Kasteelpark Arenberg 10, B-3001 Leuven-HeverleeBelgium

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