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RaziCTF Listen-Steganography

·1 min

Beginner-Intermediate CTF that took place on Oct 28. We came 15th :).

This is the writeup for Listen, an audio steganogrpahy

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Challenge description

Listen carefully, what do you hear? Look closely, what do you see? To Submit the flag, put it in UPPERCASE and in this format RaziCTF{}. like this: RaziCTF{FLAG}

We are given a wav audio file. Most audio CTFs are similar so I proceeded to open the wav file with Audacity.

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I like to open my audio files as spectograms for better visibility. When I played the audio I could make out 2 distinct beeps and immediately thought of morse code. In audacity, the 2 distinct beeps are separated as shown above

The short lines represent dots (.) and the longer ones represent dashes (-) in morse code. I proceeded to translate the first wave form into a series of dots and dashes as shown below

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- .... . .-. . .- .-.. ..-. .-.. .- --. .. ... ... .---- -- .--. .-.. ...-- -- ----- .-. ... ... --

Decoding as morse code we get the flag :)

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THEREALFLAGISS1MPL3M0RSSM

Submitted the flag as S1MPL3M0RSSM

Happy hacking :)