36 lines
1.1 KiB
Markdown
36 lines
1.1 KiB
Markdown
## unseen
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The main idea finding the flag is using LSB bit and steghide tools.
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#### Step-1:
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After I downloaded `nyc.png` & `morse.wav`, I tried basic `binwalk` and `strings`, but obviously it didn't work.
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<img src="nyc.png">
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#### Step-2:
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I tried to decode `morse.wav` online [here](https://morsecode.world/international/decoder/audio-decoder-adaptive.html).
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<img src="Morse_Decode.png">
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#### Step-3:
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This message gave me idea that I have to search further in image only. Using the LSB hint from the description, I found the string `42845193` at 1-bit LSB.
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#### Step-4:
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Using Steghide tool, I tried to extract data from the `morse.wav` by command `steghide extract -sf morse.wav`
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Passphrase was `42845193`
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It gave me this output:
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```
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wrote extracted data to "flag.txt".
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```
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#### Step-5:
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Something to work on. So when I opened `flag.txt`. It was blank with space, tabs and newline. So I tried to decode that using Whitespace Decoder at : https://vii5ard.github.io/whitespace/
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<img src="Flag.png">
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Voila! I had the flag there.
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#### Step-6:
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Finally the flag becomes:
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`csictf{7h47_15_h0w_y0u_c4n_83c0m3_1nv151813}` |