PicoCTF challenges : Easiest way to tackle Information : 168 (Forensics)

picoCTF challenge 168

This problem has a 41% like rate which can means its a bit complex to solve. However, It was hard for me on the first try and you know who I am when it comes to hacking. I figured out this problem requires us to understand basic steganography where data is hidden behind an image.

procedure

1. Download the cat.jpg file and view it using the more command. We are interested in the highlighted text below which depicts that the image is encrypted using a base64 encryption. Read more here on base64 encryption : “cGljb0NURnt0aGVfbTN0YWRhdGFfMXNfbW9kaWZpZWR9”

2. run the decryption command below and voila! we have the flag as :

echo “cGljb0NURnt0aGVfbTN0YWRhdGFfMXNfbW9kaWZpZWR9” | base64 -d

→ picoCTF{the_m3tadata_1s_modified} ← Flag

simple code to decrypt the files

Follow-up notes

Read on how to use steighide linux program that helps us to extract information encrypted on images using advanced methods.

On to the Next!