Cryptanalysis of secure arithmetic coding

This work investigates the security issues of the recently proposed secure arithmetic coding (AC), which is an encryption scheme incorporating the interval splitting AC with a series of symbol and codeword permutations. We propose a chosen-ciphertext attack which is capable of recovering the key vectors for codeword permutations with complexity O(N), where N is the symbol sequence length. After getting the key vectors for codeword permutations, we can remove the codeword permutation module, and the resulting system has already been shown to be insecure in the original paper.