Man-In-The-Middle Attack against Certain Authentication Protocols Revisited: Insights into the Approach and Performances Re-Evaluation

Abstract

We address a class of authentication protocols called “HB” ones and the man-in-the-middle (MIM) attack, reported at the ASIACRYPT conference, called OOV-MIM (Ouafi-Overbeck-Vaudenay MIM). Analysis of the considered attack and its systematic experimental evaluation are given. It is shown that the main component of OOV-MIM, the algorithm for measuring the Hamming weight of noise vectors, outputs incorrect results as a consequence of the employed approximation of the probability distributions. The analysis reveals that, practically, the only scenario in which the OOV-MIM attack is effective is the one in which two incorrect estimations produced by the algorithm for measuring the Hamming weight, when coupled, give the correct result. This paper provides additional insights into the OOV-MIM and corrected claims about the performance/complexity showing that the performances of the considered attack have been overestimated, i.e., that the complexity of the attack has been underestimated. Particularly, the analysis points out the reasons for the incorrect claims and to the components of the attack that do not work as expected.