Correlation Power Analysis Against Stream Cipher MICKEY v2

In this paper we discuss correlation power analysis attack against stream cipher MICKEY v2. In such attacks, we use Hamming-Distance model to simulate the power consumption. Hamming-Distance model is a more accurate description to power consumption than other models such as Hamming-Weight, bit model etc. Generally, Hamming-Distance model is used to map the transitions that occur at the cells’ outputs of a CMOS circuit to the values of power consumption. In our attacks, we propose the Hamming-Distance model based on internal nodes of XOR gates considering that the basic structure of MICKEY v2 is a two-input and a three-input XOR gate. We simulate the power which is coming from not only the output of gate but also the internal nodes. This model is more accurate than before ones because we simulate the power consumption of all transistors consumed. Then we designed the attack way to MICKEY v2 by this model. And finally we simulate the result of attacking. The result shows that it needs only few or ten power traces during initialization for us to reveal the secret key by using weakness of MICKEY v2 initialization when resynchronization.