An Algorithm for Solving the LPN Problem and Its Application to Security Evaluation of the HB Protocols for RFID Authentication

A novel algorithm for solving the LPN problem is proposed and analyzed. The algorithm originates from the recently proposed advanced fast correlation attacks, and it employs the concepts of decimation, linear combining, hypothesizing and minimum distance decoding. The proposed algorithm appears as more powerful than the best one previously reported known as the BKW algorithm. In fact the BKW algorithm is shown to be a special instance of the proposed algorithm, but without optimized parameters. An improved security evaluation of the HB protocol for RFID authentication is then developed. Employing the proposed algorithm, the security of the HB protocol is reevaluated, implying that the previously reported security margins appear as overestimated. keywords: cryptanalysis, LPN problem, fast correlation attacks, HB protocol, RFID authentication.