8 June 2019

Hsctf Forensics Coolimage2

by eshaan7

Challenge: Cool Image 2 (for 105 points, dynamic) [Forensics]

Challenge description:

Written by: cppio
My friend sent me this image, but I can't open it. Can you help me open the image?
File: cool.png
Free Hint: Try looking at the raw contents of the file.

Let’s capture tis fl4g:

We have a cool.png file, on opening it, we get,

Let’s see the hexdump of this file with the command,

$ hexdump -C cool.png

We get,

As we can see here, there’s some string in the header i.e. extra bytes that is messing up our cool.png file that’s why we are not able to open it in image viewer,
We can simply use foremost to extract the image from the messed up file we have.

$ foremost cool.png
$ eog output/png/*.png

We have the Flag!

FLAG: hsctf{sorry_about_the_extra_bytes}

Thankyou for reading, happy hackin’! ~ eshaan7