GryphonsOS

Welcome to GryphonsOS!

We are given a ppsm file which means that there is a macro running and it will auto run. However if we open the file in powerpoint, we can see a whole bunch of clues that will lead us to the flag.

Firstly, we can find out whats the order of the flag. This might not make much sense now, but it will make more sense as we go through it.

The first part, the audio file, spooky.wav.

Lets take a look at it and see if we can find any clues. By opening it in audacity, we can see the spectogram shows the following

This is in braille, for reference

Thus the first part decodes to SPECTRAL

Now, onto the second part. We are given code.py, and the value of output.txt being "ㄝㄞㄜㄨㄝㄞ"

By reversing this code, we can obtain back the missing word.

encoded_text = "ㄝㄞㄜㄨㄝㄞ"
decoded_text = ""
for i in encoded_text:
    decoded_text += chr(ord(i) - 12505)
print(decoded_text)

#Output is DECODE

Thus, we get the 2nd part, DECODE

Onto part 3 now, the maze. By writing out what each of the symbols represent after decoding them using the navy flags translator (https://www.dcode.fr/maritime-signals-code), and then tracing out the path of the maze, we can trace the answer to be S-I-G-N-A-L

Thus part 3 is SIGNAL

Onto part 4, where it seems to be a completely black image. However there is something hidden in it for sure.

By increasing the exposure, we can see the hidden message in it.

Thus giving us part 4, HIDDEN

making the flag, GCTF24{SPECTRALDECODESIGNALHIDDEN}