Level 4 - Leo's Sinister Bellow
Challenge
This is a basic forensics challenge. You are given an image file Leo’s Sinister Bellow
Solution
First thing to do in any steganography challenge is an exiftool check. This will tell you if there is anything hidden in the metadata of the image
1
$ exiftool 1.png
Unfortunately, there is nothing in the metadata. Next, we can use binwalk to check for any hidden files in the image.
1
$ binwalk 1.png
We can see that there are no files hidden in the image. This means that some other encoding technology has been used.
The description asks us the examine the image closely.
With this information we can suspect that the method used for hiding the flag is LSB encoding.
In order to perform LSB extraction, we will need some tools.
The tool I will be using is stegolsb
https://pypi.org/project/stego-lsb/
Running the stego-lsb tool on the image gives us the flag.
1
$ stegolsb steglsb -r -i Chall.png -o out.txt -n 1
1
$ cat out.txt | grep zyp
Flag
zyp{P@y_@t73nt!0n_7o_L30}