A Meet-in-the-Middle Collision Attack Against the New FORK-256

  • Markku-Juhani O. Saarinen
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4859)


We show that a 2112.9 collision attack exists against the FORK-256 Hash Function. The attack is surprisingly simple compared to existing published FORK-256 cryptanalysis work, yet is the best known result against the new, tweaked version of the hash. The attack is based on “splitting” the message schedule and compression function into two halves in a meet-in-the-middle attack. This in turn reduces the space of possible hash function results, which leads to significantly faster collision search. The attack strategy is also applicable to the original version of FORK-256 published in FSE 2006.


FORK-256 Hash Function Cryptanalysis Meet-in-the-middle Attack 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Markku-Juhani O. Saarinen
    • 1
  1. 1.Information Security Group, Royal Holloway, University of London, Egham, Surrey TW20 0EXUK

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