Cryptanalysis of the Modified Hill Cipher Algorithm using Myszkowski Transposition

Barrieta et al., authored a modified Hill Cipher algorithm to address the vulnerability of Classic Hill Cipher against Known-Plaintext attack. The said authors claimed that the modified algorithm removed the vulnerabilities of the original Hill Cipher and is resistant to Known-Plaintext attack. In this paper, the researchers intend to perform a more comprehensive analysis by utilizing Cryptanalysis Techniques and using several attacks aside from the initial tested vulnerability to further prove the strength and efficiency of the modified algorithm as well as to show that it is non-linear. Two major techniques which are Chosen-Plaintext attack and Chosen-Ciphertext attack were conducted. Analysis showed that the produced Ciphertext are completely different to each other and is non-linear in nature. In addition to the Cryptanalysis conducted, Strict Avalanche Criterion and Randomness testing were performed. Results show a 52.78
^%
yield for the Strict Avalanche Criterion followed by a Randomness Test which shows P-values greater than 0.01 for all subsequent tests, proving that the Ciphertext produced by the Modified Hill Cipher Algorithm has a high randomness result.