Cryptosystems are tested by subjecting them to cryptanalytic attacks by experts. Most of the cryptosystems that have been publicly proposed in the last decade have been broken. Some of the attacks that have been used are outlined, and some of the basic tools available to the cryptanalyst are explained. Attacks on the knapsack cryptosystems, congruential generators, and a variety of two key secrecy and signature schemes are discussed. There is also a brief discussion of the status of the security of cryptosystems for which there is no known feasible attack, such as the RSA, discrete exponentiation, and DES cryptosystems. >

Cryptanalysis: a survey of recent results

The Matsumoto-Imai public key scheme was developed to provide very fast signatures It is based on substitution polynomials over GF(2m) This paper shows in two ways that the Matsumoto-Imai public key scheme is very easy to break In the faster of the two attacks the time to cryptanalyze the scheme is about proportional to the binary length of the public key This shows that Matsumoto and Imai greatly overestimated the security of their scheme

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Fast cryptanalysis of the Matsumoto-Imai public key scheme

The Kravitz-Reed public key encryption system, a variant of the MIT system based on Galois fields, is interesting because it offers the potential of high security with efficient implementation In the letter we demonstrate that high security and efficient implementation are not, in reality, compatible goals with this algorithm Efficient implementation is subject to a short cycling attack that exposes the secret key to computation If the parameters of the algorithm are selected for high security, then the algorithm cannot be efficiently implemented

J. Gait

Papers

Short cycling in the Kravitz-Reed public key encryption system