WeChall - Training - Stegano I

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Challenge

A 4×4 pixel BMP image with hidden data. The challenge title says "This is the most basic image stegano I can think of."

Solution

Download the BMP file and read the pixel data directly — the message is stored as plaintext in the pixel bytes, not hidden with LSB steganography.

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$ curl -O https://www.wechall.net/en/challenge/training/stegano1/stegano1.bmp
$ xxd stegano1.bmp | head -5

The pixel data at offset 54 contains the ASCII message: 

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4c 6f 6f 6b 20 77 68 61 74 20 74 68 65 20 68 65
78 2d 65 64 69 74 20 72 65 76 65 61 6c 65 64 3a
20 70 61 73 73 77 64 3a 73 74 65 67 61 6e 6f 49

Decoded: "Look what the hex-editor revealed: passwd:steganoI"

steganoI