Fault Analysis of Rabbit: Toward a Secret Key Leakage

Abstract

Although Differential Fault Analysis (DFA) led to powerful applications against public key [15] and secret key [12] cryptosystems, very few works have been published in the area of stream ciphers.In this paper, we present the first application of DFA to the software eSTREAM candidate Rabbit that leads to a full secret key recovery. We show that by modifying modular additions of the next-state function, 32 faulty outputs are enough for recovering the whole internal state in time \(\mathcal{O}\left( 2^{34}\right)\) and extracting the secret key. Thus, this work improves the previous fault attack against Rabbit both in terms of computational complexity and fault number.