## Cryptology ePrint Archive: Report 2011/331

Cryptanalysis of Cho \textit{et al.}'s Protocol, A Hash-Based Mutual Authentication Protocol for RFID Systems

Masoumeh Safkhani and Pedro Peris-Lopez and Julio Cesar Hernandez-Castro and Nasour Bagheri and Majid Naderi

Abstract: Radio frequency identification systems need protocols to provide confidentiality, user privacy, mutual authentication and etc. These protocols should resist active and passive attacks such as forgery, traceability, replay and desynchronization attacks. In this paper we cryptanalysis a hash based RFID mutual authentication protocol which has been recently proposed by Cho \textit{et al.} More precisely, we present the following attacks on this protocol: \begin​{enumerate} \item \textbf{Desynchronization attack}: the success probability of attack is 1'' while the attack complexity is one run of protocol. \item \textbf{Tag impersonation attack}: the success probability of attack is $\frac{1}{4}$'' for two runs of protocol. \item \textbf{Reader impersonation attack}: the success probability of attack is $\frac{1}{4}$'' for two runs of protocol. \end{enumerate}

Category / Keywords: cryptographic protocols / RFID, Authentication, Desynchronization Attack, Tag Impersonation Attack, Reader Impersonation Attack.