ISSN 1000-1239 CN 11-1777/TP

• Paper •

### Integral Attack of Reduced-Round MIBS Block Cipher

Yu Xiaoli1,2 , Wu Wenling1, and Li Yanjun1

1. 1(Institute of Software, Chinese Academy of Sciences, Beijing 100190) 2(University of Chinese Academy of Sciences, Beijing 100049)
• Online:2013-10-15

Abstract: MIBS is a lightweight block cipher aimed at constrained resources such as RFID tags and sensor networks, which was proposed in CANS2009, by Izadi M. I. et al. There have been a few security analysis results about MIBS, such as differential analysis and linear analysis on reduced rounds of MIBS. In this paper, we give an integral attack on reduced rounds of MIBS. Firstly, a 5-round integral distinguisher of MIBS is given by considering the special property of round function. Secondly, we use the higher-order integral technology to extend the 5-round integral distinguisher by another 3-round which helps us get a better integral attack on MIBS. Finally, we attack 8-round, 9-round and 10-round MIBS using these distinguishers. Furthermore, we use partial sum technique to reduce the time complexity of the integral attack. We attack 8-round MIBS with the data complexity of 29.6 and time complexity of 235.6encryptions, attack 9-round MIBS with the data complexity of 237.6 and time complexity of 240encryptions, and attack 10-round MIBS with the data complexity of 261.6 and time complexity of 240encryptions. Moreover, the results of this paper can be applied to both MIBS-64 and MIBS-80. Finally, the higher-order integral technology can also be applied to other Feistel-SP type block cipher, which can improve the results of integral attacks.