What is it? @.@

Here is the place where I record some tactics about wargame, systems, and other security issues.

2012-10-26

Hack This Site! - Stego 3

Description:

Click here to try mission level 3


Look carefully: it's obvious, just not at first sight.
Thank you tiksi
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|_______________|check

Solution:
  1. When you click into this challenge page, you will see a gray level image like above.
  2. Since the hint "Look carefully: it's obvious, just not at first sight." tells us to look carefully, let's use a hex editor to check it out!
  3. After we opened the image, we would discover there are some differences of the hex value in the content of the image.
  4. I replaced all the '3D' with 'FF' in the image, and after that we would find out the answer is displayed on the image
  5. Enter the password! It's done!