Side-Channel Attack on a Protected RFID Card

Side-channel attack is a known security risk to smart cards, and there have been efforts by smart card manufacturers to incorporate side-channel attack countermeasures. In this paper, we study a widely used smart card that uses the 3DES algorithm. First, a platform is setup to extract the power consumption information from the electromagnetic wave. Based on the findings from the initial analysis, we determine that the card is equipped with a “head and tail protection” mechanism. Second, a chosen-plaintext power analysis with a complexity of 2
¹⁶
is proposed, which is designed to recover the second round key from the power leakage in the third round. Then, a slicing-collision-algebraic attack is presented, which decreases the complexity to 2
⁶
rapidly. The experiments show that after collecting 20000 power traces (in approximately 200 s), only
$2^{6} \times 8$
key guesses and another 177 searches (about 300 seconds) are sufficient in recovering the 56-bit source keys of DES successfully. In other words, we demonstrate how the security of the 3DES card can be easily compromised, using side-channel attacks. Finally, we recommend that the head and tail protection should extend to the first and last four rounds, at the minimal, in order to be side-channel attack resilience.