xortool

xortool is a Python-based cryptanalysis tool that analyzes and breaks multi-byte XOR cipher encrypted data by performing statistical analysis to determine the most probable key length and key values. It uses character frequency analysis, key length estimation through coincidence counting, and known-plaintext assumptions to recover encryption keys without brute force. CTF participants, malware analysts, and cryptography researchers use xortool to quickly defeat XOR-based obfuscation, which remains one of the most common lightweight encryption schemes found in malware, data encoding, and CTF challenges. The tool can process raw binary files, hex-encoded data, and text input, outputting recovered keys and decrypted plaintext with probability rankings for each candidate.