Paper 2006/480

Cryptanalysis of REESSE1+ Public Key Cryptosystem

Shengli Liu and Fangguo Zhang

Abstract

A new public key cryptosystem, called REESSE1+, was proposed. REESSE1 consists of two primitive algorithms, a public key encryptio/decryption algorithm and a digital signature algorithm. We give some analysis to REESSE1+, and show that the system is totally unsecure. We show how to derive the private key from the public key. As the same time, we also show how to forge signatures for any messages, given two valid signatures.

Note: Correct an error in the algorithm of forging signatures.