Ciphertext-Only Attack on Gentry-Halevi Implementation of Somewhat Homomorphic Scheme

  • Michal Mikuš
  • Marek Sýs
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7721)


In this paper we examine the first working implementation of a fully homomorphic scheme from C.Gentry and S.Halevi. We implemented the ciphertext-only attack from [2] using the NTL library and show that only dimensions up to 128 are feasible for common computational power. We propose also two improvements of this attack that enable us to use the fastest variant of LLL from NTL and compare the results.


Error Vector Homomorphic Encryption Short Vector Cryptology ePrint Archive Homomorphic Encryption Scheme 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Michal Mikuš
    • 1
  • Marek Sýs
    • 1
  1. 1.Institute of Mathematics and Applied Informatics, Faculty of Electrical Engineering and Information TechnologySlovak University of Technology in BratislavaBratislavaSlovak Republic

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