In this type of operation the relationship between consonants and vowels (C/VQ) is analyzed aiming to locate phonemes that can identify both the language and the construction and syntax of the original information. It is particularly useful to attack plain-text information or, as a mid layer to conduct other attacks in customized uncompressed file patterns.
It is evident that the distribution of letters, especially the most common in Portuguese and English (in red and yellow) is completely distorted and changed after encryption, preventing any successful attack of this type. Also, a pattern of similarity (1.24 to 1.25) can be seen in all cryptographic results, regardless of the text-plane used.
Therefore, this type of attack on the OBAKE-512 algorithm or the data it encrypts is completely impractical.
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