Hey Hacklido fam! sagnik17 back again with a really cool forensics challenge this time, this one genuinely got my brain going 🧠⚡
What we got
A file transmission.wav, Just an audio file. Suspicious already 👀
The hints pointed towards audio analysis so naturally I threw it into Audacity first. The regular waveform view? Pretty boring, nothing jumping out.
But then… Spectrogram view. 👇
Now we’re talking 😏 Something was clearly hiding in there, distinct high and low patterns, almost like pulses.
My Thoughts 🧠
Two levels. High and low. In the world of computers there’s really only one thing that screams two levels binary! (0s and 1s)
I manually decoded the first chunk just to verify my hunch
yes we’re onto something, but
No way I’m manually decoding the entire spectrogram 🥱, so I fed the image to Gemini and asked it to convert the visual patterns into binary. Worked like a charm!
The binary decoded was like:
01001000 01100001 01100011 01101011 ...
H a c k ...
now the last thing is to decode and add some points in the bucket
This one was genuinely satisfying — audio → spectrogram → binary → text. Beautiful chain 😄
See you in the next one ✌️
CTFsDigital ForensicsGeneralhacklido #wrap
