In this tutorial I am going to show you how we can add a dialog box to the beginning of any app. Personally, I use this trick to help out my fellow co-workers, either giving them subtle reminders (“You have used deodorant today, right?”) or even helpful messages (“Are you sure you want to format your hard drive?”). We will be using a special technique called a code cave. I will not be going into great detail about code caves as I plan on covering them in my normal beginner’s guide to reverse engineering series, but along with the files in the downloads for this tutorial I have included a great document on code caves and how to use them.

The tools you will need for this tutorial are OllyDBG (any version), ODBGScript plugin (included in the download), “Code Cave Finder” script for Olly (also included in download), CFF Explorer (or any PE editor- you can download CFF from the tools page), and the target file called “ColorPicker”. A computer will also come in handy.

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