Paper 2013/825

EPCGen2 Pseudorandom Number Generators: Analysis of J3Gen

Alberto Peinado and Jorge Munilla and Amparo Fúster

Abstract

This paper analyzes the cryptographic security of J3Gen, a promising pseudo random number generator for low-cost passive RFID tags. Although J3Gen has been shown to fulfill the randomness criteria set by the EPCglobal Gen2 standard and is intended for security applications, we describe here two cryptanalytic attacks which question its security claims: i) a probabilistic attack based on solving linear equation systems, and ii) a deterministic attack based on the output sequence decimation. Numerical results, supported by simulations, show that for the specific recommended values of the configurable parameters, a low number of intercepted output bits are enough to crytanalyze J3Gen. We then make some recommendations which address these issues.