Upload:
1:23 AM 02/28/2024
Description
Try to keygen this. Good luck!
Programista on 8:22 PM 03/02/2024: Solved.Have a nice day.
nightxyz on 2:51 AM 03/03/2024: Use latest ILSpy.
YAY - GOOD JOB
SirWardrake on 4:08 PM 03/04/2024: Damn it. I tested with dnSpy, it didn't give me the code. With ILSpy it's an easy task.
After some research I found out, that I could use a packer and obfuscator to hide the code. BUT I also learned, that nearly all of them could be bypassed in seconds.
So, is there a way to obfuscate the C#-code properly? Or is it all snake-oil and it's best to NOT use C# for crackmes?
cnathansmith on 5:21 PM 03/05/2024: @SirWardrake There are obfuscators specifically for C# and of course there are binary packers and wrappers, but you start to get into territory of making them so complicated they're not really fair challenges at that point.
If you want to use C#, then the fun thing would be to look into really obscure features of the languages you could abuse, or do some research and reversing to see how some objects are represented in memory at a low level and do some kind of direct manipulation/type confusion things.
It would challenge you and the players to dig down and learn how some of these things specific to the language work. I find them fun with no patching or plain text passwords showing up in memory at any point, so you have to work out the actual routine performed on the input to reach the success outcome
SirWardrake on 8:49 PM 03/06/2024: @cnathansmith Thank you for your support. I will dig into this approach. I think, I will stick with C++ for the time being until I am more familiar with the subject matter.
jeffli6789 on 7:46 AM 03/15/2024: Hi @SirWardrake, dnSpy appears to be unable to show the code (or even recognize the file as .NET) because of the way you compiled it (which might be intentional or unintentional). If you use Detect it Easy to check the file, you can find there is an overlay PE file at offset 0x25000. You can dump this file and load it with dnSpy, and see all of you code in it.
justAuser on 6:57 PM 03/21/2024: using System.Collections.Specialized;
static int GetModifier()
{
int dayOfWeek = (int)DateTime.Now.DayOfWeek;
int day = DateTime.Now.Day;
return ((int)Math.Pow(day, dayOfWeek) ^ (day * dayOfWeek)) % 26;
}
static string GetMath(string str_1)
{
string text = "";
string text2 = "";
for (int i = 0; i
acidea on 4:32 PM 04/02/2024: @jeffli6789 Hello, Can you write a solution?
bang1338 on 8:34 AM 04/14/2024: Solved!
slither on 2:23 AM 02/18/2025: can anyone instruct me on editing the code in VS?
for some reason it doesnt work on dnSpy
thanks
ds: helloThere4813
You must me logged to submit a solution
Solution by bang1338:
A walkthrough of my solution.
In zip file contain:
- Keygen project file
- Bunch of image
- ACTUAL keygen (compiled, not obfuscated, feel free to decompile keygen.)
- a markdown, which is my walkthrough and solution. Require a GitHub-like markdown reader like Markdown Monster