A modified McEliece public key encryption system with a higher security level

In the traditional wiretap scenario, we analyse the equivocation of the eavesdropper under different attacks when the legitimate parties employ the McEliece public-key cryptosystem. The analysis in this paper is not on the best attack to break the cryptosystem but on the information leakage. We show that there is considerable information leakage to the eavesdropper under Brickell´s attack. We also propose a modified McEliece public-key cryptosystem to reduce the information leakage under Brickell´s attack. We prove that the modified system exhibits zero information leakage under Brickell´s attack, and the price for this higher security is a lower information rate.