L-P States of RC4 Stream Cipher.
Jing Lv, Dongdai Lin · IACR Cryptology ePrint Archive · 2013
The stream cipher RC4 was designed by R.Rivest in 1987, and it is a widely deployed cipher. Many predictive states of RC4 for some special indices i were presented in the last 20 years. In this paper, we present several long term predictive states. These states increase the probability to guess part of the internal state in a known plaintext attack and present a cryptanalytic weakness of RC4. This paper also analyzes possible long term bias in the keystream and further propose a search method for the long term predictive states.