08 Jun 2016

What’s wrong with this file – ASLR is tricky!

I love magic tricks. My absolute favorites are "there's nothing up my sleeve" kind of tricks. You can look at the equipment, you can examine magicians outfit, everything seems fine - yet the rabbit magically appears and disappears.

Here's a similar reversing challenge for you: https://www.mediafire.com/?38evlc6gmyieskn

This EXE file contains relocations. It has all the necessary necessary flags in PE header. And it gets ASLR support in Windows 10, as you can see in picture:
But on Windows 7/8.1 this poor executable will be always loaded at it's preferred imagebase 0x400000, and doesn't get ASLR support:
Can you figure out what's so special about it? smile

I will provide the correct answer in one week. Or you can provide your opinions in comments. Extra respect awarded for detailed answers and explaining how you figured that out. Extra extra respect if you knew the answer even before looking at the executable. smile