Efficient Reconstruction of RC4 Keys from Internal States
نویسندگان
چکیده
In this paper we present an efficient algorithm for the retrieval of the RC4 secret key, given an internal state. This algorithm is several orders of magnitude faster than previously published algorithms. In the case of a 40-bit key, it takes only about 0.02 seconds to retrieve the key, with success probability of 86.4%. Even if the algorithm cannot retrieve the entire key, it can retrieve partial information about the key.
منابع مشابه
On Reconstruction of RC4 Keys from Internal States
In this work key recovery algorithms from the known internal states of RC4 are investigated. In particular, we propose a bit-by-bit approach to recover the key by starting from LSB’s of the key bytes and ending with their MSB’s.
متن کاملHow TKIP Induces Biases of Internal States of Generic RC4
RC4, designed by Rivest, is widely used including WPA, which is one of the security protocols for IEEE 802.11 wireless standard. The first 3-byte RC4 keys in WPA generated by IV are known since IV can be obtained by observing a packet. In 2014, Sen Gupta et al. found linear correlations between the keystream byte and known RC4 key bytes. In 2015, Our previous work extended linear correlations t...
متن کاملA New Class of RC4 Colliding Key Pairs with Greater Hamming Distance
In this paper, we discovered a new class of colliding key pairs of RC4, namely, two different secret keys generate the same internal state after RC4’s key scheduling algorithm. This is to our knowledge the first discovery of RC4 colliding keys with hamming distance greater than one, that is, the colliding key pairs we found can differ from each other at three different positions, and the value ...
متن کاملGeneralized Classes of Weak Keys on RC4 Using Predictive State
Conventional class of weak keys on RC4 stream cipher is defined as a specific case that combinations of the first three bytes of secret key satisfy two relational equations. This paper expands and generalizes the classes of weak keys using generalized relational equations and special classes of the internal state (called predictive state). We derive the probability that generalized classes of w...
متن کاملAnalysis of Non-fortuitous Predictive States of the RC4 Keystream Generator
The RC4 stream cipher is the most widely used software based stream cipher. It is based on a secret internal state of N = 256 bytes and two pointers. This paper proposes an efficient algorithm to compute a special set of RC4 states named non-fortuitous predictive states. These special states increase the probability to guess part of the internal state in a known plaintext attack and present a c...
متن کامل