Enhanced Cryptanalysis of Substitution Cipher Chaining mode (SCC-128)

In this paper, we present an enhanced cryptanalysis of the Substitution Cipher Chaining mode (SCC) [1]. In [2], SCC-128 (SCC which uses AES with 128-bit key) was broken using 5 attacks, where the authors used an active attack model (where the attacker can force the disk encryption application to re-encrypt a sector for her), the complexity of these attacks are at most 2 cipher executions. In this paper, we enhance the main attack on SCC-128, this enhancement decrease the complexity of SCC-128 attacks to be at most 2 cipher executions. We also cryptanalze SCC-128 in a less restrictive attack model, our attacks are upper bounded with 2 cipher executions.