Clear it in 3 steps
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Start the environment
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Investigate the target
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Submit the flag
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Data Hidden in Audio File
Mission
`hidden.wav` hides a message encoded with on-off keying (OOK). Turn the tone on/off slots into bits and decode them to recover the flag (the bundled `decode.py` is a reference implementation).
Hints
Hint 1 Show
The beeps in hidden.wav are on-off keying (OOK): each 40ms slot is tone ON=1 / OFF=0
Hint 2 Show
Read samples with Python's wave module and threshold the per-slot peak amplitude into bits
Hint 3 Show
Skip the leading 8-slot sync preamble, pack the rest into bytes MSB-first and ASCII-decode for the flag (no FFT; the bundled decode.py implements this)