cryptoPromedium

Hell is haard

bluehensctf

Task: a JSON array of 2048 integers hides a message behind a Haar-based encoding and extra byte scrambling. Solution: recursively apply the inverse unscaled Haar transform, convert the recovered samples to bytes, then fix each 512-byte block with the correct modulo-256 rotation to reveal the flag.

$ ls tags/ techniques/
jsonwaveletplaintext_recoveryhaar_transformbyte_rotation
inverse_haar_transformrecursive_signal_reconstructionblockwise_byte_shift_recovery
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