RSS
 

Posts Tagged ‘file header’

HACKvent 2019: Day 1

02 Dec 2019
CTF: Hackvent 2019
Link to challenge: https://academy.hacking-lab.com
Date Completed: 2 December 2019

Challenge

HV19.01 censored

Solution

The hint indicates that we should have a clearer smaller image available to us.
At first we attempt to shrink the image, resharpen and enlarge but there is too much degradation for that to work. We also open the image in GIMP and mess with levels/contrast with no luck.

Finally, we use binwalk on the image to find hidden binaries and find:

We extract the second JPEG image in this file which gives us a smaller preview thumbnail but with a crisp QR code!


This image is good enough to scan and gives us our flag!

Flag:  HV19{just-4-PREview!}

 
No Comments

Posted in Hackvent 2019