KeygenMe

Difficulty: ?/10 (I will let you guys decide but it's definitely not for beginners)
Language: C++
Platform: Windows
OS Version: Tested on Windows 11 64-bits
Protection: Dhaedalida 1.0.0.2 (Custom Packer + Custom VM + anti-debug + anti-tamper)
Description
Hi all,
I have always been a big fan of software protectors specially those with obfuscation / virtual machine features like Themida / VMProtect among others so after a long time I've decided to make a new one and I'd like to see how it holds up against people who actually know what they're doing so here's a small keygenme protected with it. Genuinely curious about your feedback and I am looking forward for your write-ups.
The VM is not a traditional one like Themida / VMProtect (neither like my old VM posted here 10 years ago, wow time flies) but something else that I read on a paper and I wanted to implement some ideas of it and more I would like in the future (I'm not going to say more as to not spoil the fun).
Goals
Bronze: Unpack & patch it so every username / password will be accepted.
Silver: Generate a working username & serial pair.
Gold: Generate a fully working keygen for any username.
SHA-256 (.exe): 686414068984BAF182AB7F5FCCF91EC49CADB76BEE9AFBFA6C4E728C22A32112
Have fun and please share your findings.
Holy

Not much to say there. Valid solution is a keygen that produces a valid key for any given name.
Binaries for Linux and Windows are provided. Plain C, no symbols stripped, compiled with -O0, so should be fairly easy to follow.
Difficulty is medium. Or perhaps easy for someone with some math knowledge. Here are some valid keys:

Name: hekliet
Key: 3fec806bc9ce82d4c00ee01af273a0b5
Name: Tuts 4 You
Key: 40105e5bb69056bd3fdc1a4496fa9430
Name: Guybrush Threepwood
Key: 400e09a63ee6d3a2bfd94d31f7369d10

This one uses the built-in license system of the ArmDot .NET..
Provide a serial or an unpacked or a patched variant that accepts a serial.

Difficulty: 5
Language: C GCC
Platform: x64
OS Version: Windows  10+
Packer / Protector : Selfmade

Description :
Implement keygenme that generate a serial derived from a nickname. Also demonstrate a generator that, given a nickname, produces the correct serial.
I used my own tool that I've been developing for two years. It started as an optimizer, but I’m now experimenting with the reverse idea — using it to help with obfuscation and code retranslation.

Hint: MD5(UsernameUpper + ':' + salt), take first 16 hex chars, format as XXXX-XXXX-XXXX-XXXX.

Hey there!
I made this KeyGenMe because I enjoy playing chess.
This challenge is written in .NET and involves some mathematical operations, mixed with a few chess-related twists. Your task is to figure out the logic behind generating a valid serial key based on the username you enter. But be warned—it’s not as simple as just moving a pawn forward ( maybe a hint )
Protection used : None.
Goals :
1. Provide valid combination for Username - Serial Key ( Bronze )
2. Fully KeyGen it - every username with different serial key algorithm ( Silver )
3. Full KeyGen plus EXPLANATION on what u did and how you figured out everything ( Gold )
Good luck!

This is a simple MD5 Hash keygenme.
It is protected with the themida.

VSEC KeygenMe #2
What you have to do:
I hope peoples who interested in Reverse Engineering learns something from this type of challenges.

Best Regards.
 

Simple Code Virtualization KeygenMe ( Not Commercial VM )
Try to find Algorithm and make correct key 
It's not too hard
Your opinions about VM Complexity are welcome.

Thanks

I have provided a zip archive which contains two .py files, as seen in the screenshot. In LicenseChecker.py there is a validation function invoked by main.py where you put the key in the given format.
The python code is obfuscated using a obfuscator I'm currently working on. If you solved the challenge, or have any feedback to give, or need hints/help with reversing without spoiling, please let me know. Thanks.
 
You can see original source code and the solution in the 'Authors Code' and 'Authors Solution', if you wish.
Good luck!

A simple console application that displays the HWID and asks you to enter an "activation key" for it.
Key format: xxxxxxxx-xxxxxxxx-xxxxxxxx-xxxxxxxx-xxxxxxxx-xxxxxxxx-xxxxxxxx-xxxxxxxx-xxxxxxxx-xxxxxxxx
The solution will be a description of the algorithm to generate an activation key for any HWID value (there is no need to write code).

P. S.
Archive password: 123

Here is a keygen challenge I got recently. This one requires to find the coefficients of a 26th degree polynomial that sums up to a specific value. A valid serial is also provided. The challenge is to code a keygen with least / reasonable time complexity without patching anything.
Update: Added my initial code that barely works. Please let me have your suggestions to improve the code.

This is a little past time project I have been working on, here I put an interesting spin to conventional c# obfuscation.
Try to unpack this file or at least keygen it.

Your goal is to create a keygen and make a tutorial and/ or write instructions about the steps done by you.
What is C++/CLI?
C++/CLI is C++ support .NET framework to make managed application run on .NET framework.
https://en.wikipedia.org/wiki/C%2B%2B/CLI
Feel free to post your solutions.

Crack and keygen this for training your skills. It is protected with ConfuserEx using some anti tricks.
Write a tutorial and document the methods used in your solution.
My Anti-virus engine detects it's a virus, but it's not.
 

I coded a keygenme, simple tricks.
I hope you enjoy your time trying to solve this!

Provide a valid serial and User ID or make a keygen. Good Luck.

Provide a valid pair of name and serial, or write a keygen.
Good luck.

Hi
I got this keygenme in my hard drive, this is from CIN1TEAM and created by MR. Teo. 
Thought this might help someone to test his keygenning skill.
 
Thanks

Only simple algorithms - for one name one key.
Provide a valid pair of name and serial, or write a keygen.
Good luck.
 

The real goal is to make a keygen capable of generating infinite valid combinations of name and keys. 
Btw, also a valid serial is appreciated
The only protection used is renaming.
Good luck!
@kao Long time no see 🧐