Cryptography - morse-code - writeup

description

Morse code is well known. Can you decrypt this? Download the file here. Wrap your answer with picoCTF{}, put underscores in place of pauses, and use all lowercase.

writeup

Opening the file in ghex or sonic visualizer did not help

After reading the following article I decided to try to open it using audacity.

https://dropn0w.medium.com/do-the-loop-downunderctf-2021-5d8ee86c0f2b

Next I tried to interpret the waves as morse code.

I can see that there is a long pattern consisting out of dashes and dots. It looks like this:

I ended up with the following morse code:

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

Using cyberchef ‘From Morse Code’ I end up with the following string:

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WH47H47H90DW20U9H7

Since the task says “Wrap your answer with picoCTF{}, put underscores in place of pauses, and use all lowercase.”

I ended up with the following flag:

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picoCTF{wh47_h47h_90d_w20u9h7}