Related-key impossible differential attacks on 8-round AES-192

In this paper we examine the strength of AES against the related-key impossible differential attack, following the work of Jakimoski and Desmedt [12]. We use several additional observations to substantially improve the data and time complexities of their attacks. Amongst our results, we present a related-key attack on 7-round AES-192 with data complexity of 2 56 chosen plaintexts (instead of 2(111)). Our attack on 8-round AES-192 has data complexity of 2(68.5) chosen plaintexts (instead of 2(88)). The time complexities of our attacks is also substantially lower than the time complexities of previous attacks.