On the security of an ECC based RFID authentication protocol

Following the fact that there are some efficient implementations of ECC-based RFID authentication protocols on RFID tags, a new family of RFID authentication protocols known as EC-RAC family has been introduced. However, it has been shown that all the versions of EC-RAC protocols are exposed to privacy and/or security threats. In this paper we analyzed a version of the EC-RAC RFID authentication protocol as well as a version of Schnorr protocol which were presented in a recent work and are claimed to have the demanding requirements. We demonstrated an impersonation attack on the claimed improved EC-RAC, and consequently showed that it would not satisfy the tag authentication property. Also, we showed that the improved Schnorr protocol does not provide the untraceability feature. Moreover, we discussed the inherent problems of the claimed protocols and why they fail.