Posted by: nickfnord | January 24, 2009

My First Crackme

I wrote my first crackme this week.

it can be found here:

here’s the description:

An experiment in obfuscation – by Nick Fnord

Date: 24-Jan-2009
Program Type: Consol application
Crackme Type: KeygenMe/Analysis
Difficulty Level: I think this is a 3 or 4 but as it’s my first
crackme I’m unsure.
Programming Language: C++ with a bit of inline ASM
Platform: Only tested on WinXP but as I have included the
DLL’s statically it should run on anything that
supports the PE format.

Hi All,

This is my first crackme. I made it as an excercise in obfuscation and also
to experiment with some various anti-debugger techniques. I don’t think there
is a plug in to olly that successfully takes care of all the methods I used,
but if there is, I’d be interested to know about it.

The application will ask for a username and password, and if correct will
display a fairly well known poem.

Task One:
Your Primary task is to write a Keygen program for it. You are permitted to
do whatever you like to the original program.

Task Two:
Write a tutorial detailing how you went about making the keygen. Ideally,
Describe the program in High-level pseudo-code or in words, identifying all the
anti-debugger methods used.

Hope you have many hours of enjoyment from this one.

Nick (NickNOSPAM[at]nickfnord[dot]com)

That pretty much sums it up. I’m quite interested to see what other people think about it and whether they rate the program higher or lower than the 3 I gave it. Most of it was written with a glass of at hand so it’s perhaps not the most efficient bit of code I’ve made, but still 🙂

I offer a free cross link on this blog to the first person to crack it 🙂




  1. I have a few questions about InfoSec Institute’s online reverse engineering training course; could you please contact me by email, or reply with an email address? Anonymized mail suits me just fine.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s


%d bloggers like this: