Need to crack a substitution cipher?
I just published Vsolve - a solver for substitution ciphers. It implements the Jakobsen’s algorithm to perform a bigram analysis of the ciphertext, find the most probable key and get the plaintext without knowing the key. The tool does things that I missed in other tools, mainly it’s: cross-platform - CLI tool written in Rust, extensible - adding a new language is just a matter of adding a config file, and capable - full UTF-8 support, built-in IoC calculator and the list goes on.
NOTE: The code is NOT optimized for speed, more for readability and extensibility - you don’t usually have to crack hundreds of megabytes of text during a CTF.
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