Tags: png misc 

Rating:

## Description

The cat is hiding somewhere. Where is the cat?

[cat.png](https://ctf.bamboofox.cs.nctu.edu.tw/files/35fd27d8c649e6d0954b429ed9fa680d/cat.png?token=eyJ0ZWFtX2lkIjozMSwidXNlcl9pZCI6NjgsImZpbGVfaWQiOjl9.Xg64OA.CESszBPmEtsVlxvd54TzjmNnAZw)

## Solution

You can get `cat.png` from the Problem.

use command `binwalk` to get information from the header, then you will find out some "Zlib compressed data" inside.

use command `foremost` to recover the image , you will get other two images and also have zlib inside, respectively.

use the command below to see the difference between two images in pixels.
```
compare 00000000.png 00000725.png -compose src diff.png
```

and you will get the QR code. (link: [https://imgur.com/download/Xrv86y](https://imgur.com/download/Xrv86y))

After scanning the QR code, you can get the final image, using any text editor or command `strings` to find the flag inside.

**BAMBOOFOX{Y0u_f1nd_th3_h1dd3n_c4t!!!}**

Original writeup (https://github.com/MacacaHub/CTF-writeups/tree/master/BambooFoxCTF2019/Find%20the%20Cat).
SovietBeastJan. 1, 2020, 12:24 p.m.

Hey, may I ask you how to get the compare command I now its newb question but Im searching and I cant find that 'compare', there is build-in cmp and diff but it didnt produce output that satisfy me