## Difficulty Easy ## Category Steganography ## How To Solve From the filename it should be clear that LSB is a hint, referring to the Least Significant Bits from which you have to extract the flag. Using Python: ```python import wave wav = wave.open("lesfilLeSduBorddemer.wav", mode='rb') frames = wav.getnframes() bytes = bytearray(list(wav.readframes(frames))) # Replace each frame_byte with only the value of the LSB for i in range(len(bytes)): bytes[i] = bytes[i] & 1 # bitmask with 00000001 # Byte array to string result = "" for i in range(0, len(bytes), 8): byte_chunk = bytes[i:i+8] int_value = int("".join(map(str, byte_chunk)), 2) char_value = chr(int_value) result += char_value # Remove the trailing '#' characters decoded = result.split("#")[0] print(decoded) # This will show the flag wav.close() ``` ## Flag `IGCTF{Th1s_m3ss4ge_1s_h1dd3n_1n_4ud10}`