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CrackMe for Java-developers

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Hi, guys!
We have developed a very good licensing system as we think.
So we'd like to start some kind of contest to hack the system.
We prepared the crackme.jar which is available on: https://licel.ru/crackme.jar

How the applet works?
It has only CLI. So you can start it in Console/Terminal: $ java -jar crackme.jar
When it starts the first time it will ask you for the activation code, the code will be validated on-line by Licel's Licensing Server.
If you enter the correct activation code: the license will be generated and the applet will work correctly.


1) The competition starts 20 of January 2012 and ends 10 of February 2012
2) The first who would hack the system will receive iPad 2 (Wi-Fi + 3G)
3) Feel free to cooperate with somebody, to discuss etc.
4) The first thing you should do if you hacked our crackme is send us the solution of how to hack :)
5) If the applet starts correctly it will show you instructions of how to get your iPad
6) By participating in the contest, you do not violate the law

We wish you a good luck!

Looking forward for your feedback.

Sorry if I have mistakes in text, English is not my native language and I didn't learned it enough :(

Sincerely yours,
Ivan Kinash, CEO
Licel LLC
Published at DZone with permission of its author, Ivan Kinash.

(Note: Opinions expressed in this article and its replies are the opinions of their respective authors and not those of DZone, Inc.)



Jonathan Fisher replied on Fri, 2012/01/20 - 3:46pm

The provided jar is obfuscated, which I guess is fine, if you're just trying to challenge people. But if your intent is to prove out your activation scheme, you should probably provide an un-obfuscated one.

Ivan Kinash replied on Sat, 2012/01/21 - 6:15am in response to: Jonathan Fisher

Thank you for your comment!

After the contest we will:
  • post an article with full description of how our protection system works
  • upload un-obfuscated jar
  • provide the access to the managing interface

We planning to start one more contest where you will be able to get promo licenses for our product Stringer (we will announce it soon).

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