"Easy as 0,1,1,2,3" is a steganography puzzle box.
There is a flag file containing a key and contact information to send it to as proof of your solution.

(Based on an art-zine we did in the mid '00s)

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*****COVER FILE

There are 4 clues. In the text of the cover, "Secrets REVEALED! (in b&w)" is the first and MOST important clue. The next somewhat visible clue is the "CDS" hidden in the barcode.

Stegsolve or threshold adjustment reveals, to white, the word "steghide" near the barcode, and "exiftool >" in a black area in the picture background.

Using "CDS" as a steghide password produces credits.jpg.

Getting info on the file reveals another image is appended to the cover file. Foremost will break these images apart. Binwalk will not only separate the images, but also separate the custom thumbnails added to each image of the stack (using exiftool, thus the clue). Regardless, these processes will produce the Baptist file.

*****CREDITS

The text hints that this is the file the flag is hidden in, and this all should be confirmed when the word "steghide" is revealed across the whole page by using Stegsolve or thresholds.

The password is revealed later.

*****Thumbnail Two - YOU ARE HAPPY!

Stegsolve or thresholds reveals the word "was" in the white area.

*****Thumbnail Three - Don't worry! INSURANCE!!! (Competition is Good!)

Stegsolve or thresholds reveals the word "here" in the white area, and "TOOL" in the black as the other letters in the sign fade.

If you use "TOOL" as a steghide password, the tool.txt file is produced.

*****tool.txt

This is a python script that will separate the cover file from the one appended to it, just as Foremost would - except the file's actually called baptist.jpg now.

*****Baptist

The text is a contextual hint to what's revealed with Stegsolve or thresholds in the white area of the image. The word "steghide" appears on the right next to an arrow pointing at the kneeling man's head (another contextual clue). Using "John" as a steghide password produces the thumb01.jpg file.

The "EXIFTOOL" clue is only relevant if you used the script from the tool.txt file, hinting there's a custom thumbnail (appended with exiftool). Again, binwalk reveals all of the files, strictly appended and thumbnails, so then this clue turns into noise.

*****Thumbnail One - Depressed? PILLS! (Competition is Good!)

Stegsolve or thresholds reveals the words "Mefa Kane" in the white space.

*****SOLVE

Use "Mefa Kane was here" as the steghide password for credits.jpg to produce the flag.

*****THANK YOU FOR PLAYING****************************************
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