Challenge of Reverse Engineering
Try a challenge or contribute your own, any platform or operating system...
The creation of new topics is disabled in these subforum categories.
Please create and post your new challenges in the appropriate subcategory of Downloads > Challenge of Reverse Engineering
A topic will then automagically be created and posted in these forums...
-
Example CrackMe - Debug Blocker x64 This is an example for submitting a CrackMe in the Downloads section of the site. You can download the file and run Debug Blocker x64. Nothing too exciting will happen! The challenge here would be to patch the debug-blocker function so that it does not spawn a second process. File Information Submitter Teddy Rogers Submitted 02/23/2020 Category CrackMe View File
-
Brute-Force Polynomial for Coefficients. 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. File Information Submitter Benten Submitted 11/14/2022 Category KeygenMe View File
-
- 1 reply
- 5.5k views
- 1 follower
-
-
Language : C++ Platform : Windows OS Version : Windows 10 Packer / Protector : Themida 3.0.3.0 Description : Looks like Oreans just dropped Themida 3. They've been working on the beta version for more than a year and just announced the initial release, so I'm praying I don't get my personal license revoked :^( Strings are (supposedly) virtualized then encrypted. The main protection is starting at VM_DOLPHIN_RED, though other VMs can be requested. Unpack/devirtualize the file. Screenshot : Themida Crackme_protected.exe
-
-
- 8 replies
- 35.2k views
- 1 follower
-
-
.NET Reactor v7.5.9.1 (Aggressive Settings + Custom Anti-Tamper) Hey everyone, I put together a small challenge for anyone interested in reversing .NET protections. This one is packed using .NET Reactor v7.5.9.1 with some pretty aggressive settings, along with a bit of custom anti-tamper logic on top. Your goal is to unpack the application and recover a clean, working assembly. Protections Enabled NecroBit String Encryption Obfuscation Anti ILDASM Hide Method Calls Code Virtualization Anti Tampering Anti Debug Merge Enums Control Flow Obfuscation (Level 9) Additional Protections Custom runtime anti-debug Anti-injection checks Integrity verification A background watchd…
-
-
- 16 replies
- 3.3k views
- 1 follower
-
-
Level: 6/10 ? Language : MASM Platform : Windows 32 bit OS Version : Tested on Win10 only, Win 7 and 8 also probably work Packer / Protector : None Description : Mostly simple math algorithms; it includes one relatively small hash part that's mostly isolated, so you can choose to ignore that part and focus on the remainder of the serial. I reckon the number of valid serials will be relatively low. Hopefully I made no big mistakes. Provide a valid pair of name and serial, or better yet write a keygen Good luck. Screenshot : KeyGenMe#1.v1.7z Keygenme template by Ziggy.
-
Difficulty : 8 Language : C/C++ Platform : Windows 32-bit and 64-bit OS Version : All Packer / Protector : Themida 2.4.6.0 Description : The objective is to interpret and reconstruct 3 procedures in each file that have been virtualized. No additional options have been used. The virtualized functions will execute when keys '1', '2' and '3' are pressed, respectively. 1 = WHITE 2 = RED 3 = BLACK Only one "brand" of VM has been used per file. I will upload additional ones when current challenges have been solved or seriously attempted. Detailed information of the interpreting procedure/internals or a complete solution paper is …
-
-
- 23 replies
- 37.8k views
- 2 followers
-
-
Nuitka 2.1.5 (Python 3.11) Hi Nuitka compiled python 3.11 file Correct password doesn't important Just patching Thanks File Information Submitter Sh4DoVV Submitted 04/18/2024 Category CrackMe View File
-
-
- 9 replies
- 10k views
- 3 followers
-
-
ArmDot .NET v2026.1 File protected with Hide strings Obfuscate control flow Obfuscate names Obfuscate namespaces and some virtualization accepted solution - unpack OR tell what is doing. File Information Submitter whoknows Submitted 01/30/2026 Category UnPackMe (.NET) View File
-
-
- 3 replies
- 1.3k views
- 3 followers
-
-
r00t0 KeygenMe v4 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. File Information Submitter r00t0 Submitted 11/02/2025 Category KeygenMe View File
-
-
- 4 replies
- 2.7k views
- 2 followers
-
-
VMPLicenseProtector This is a recently developed recreational utility. I'm unsure which forum section is appropriate, so moderators please feel free to move it if necessary. The tool implements a combined The Enigma and VMProtect protection scheme and is designed for applying VMProtect to Win32/Win64 executables and DLLs without requiring source code. It is not compatible with .NET assemblies. The interface supports Chinese/English language switching. To function, VMProtect_Con.exe must be placed in the tool's directory. Note that the tool itself is incompatible with Windows 7 and requires the DirectX 11 runtime to be installed. Software protected with it remains compati…
-
-
- 9 replies
- 6.1k views
- 4 followers
-
-
Eazfuscator.NET v2025.01 File protected by eazfuscator v2025.01 having Code Virtualization enabled. Find registration combination and reply it with the success message! File Information Submitter whoknows Submitted 07/22/2025 Category UnPackMe (.NET) View File
-
-
- 15 replies
- 6.9k views
- 2 followers
-
-
AgileNET v6.6.0.4.2 AgileNET (code virtualization on 1 method only, no other protector features used) File Information Submitter whoknows Submitted 11/11/2023 Category UnPackMe (.NET) View File
-
-
- 10 replies
- 19.4k views
- 3 followers
-
-
hekliet keygemne #1 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 File Information Submitter hekliet Submitted 03/17/2026 Category KeygenMe …
-
-
- 1 reply
- 1.5k views
- 1 follower
-
-
Themida v3.1.4 (x32 & x64) - Impossible Two files are protected with an old version Themida (3.1.4) Entry Point is virtualized Just find and restore OEP, recover the IAT and unpack if it possible Virustotal detects it as a virus, but my AV software is not File Information Submitter fReestYler Submitted 05/10/2025 Category UnPackMe View File
-
-
- 3 replies
- 6.6k views
- 1 follower
-
-
DNGuard HVM v4.93 So this is my first upload - I hope I am doing this right. I have included all the protections in the screenshots being used. Good luck File Information Submitter Visual Studio Submitted 11/11/2025 Category UnPackMe (.NET) View File
-
-
- 12 replies
- 7.2k views
- 3 followers
-
-
Eazfuscator v2021.1 Unpack and/ or provide a valid serial. Archive password : superfrog File Information Submitter whoknows Submitted 07/14/2021 Category UnPackMe (.NET) View File
-
-
- 17 replies
- 28k views
- 2 followers
-
-
VMProtect v3.8.1 Ultra (Mutation + Virtualization) The target is an old software (from 2010) coded in c++, I just apply the VMP protection without any special code as I show in the two screenshots. All available protection features in VMProtect were used with this unpackme. Refer to the attached images for the specific protection settings used. Challenge is to unpack the file, providing an explanation and details on your methodology. File Information Submitter X0rby Submitted 04/17/2023 Category UnPackMe View File
-
-
- 22 replies
- 29.7k views
- 3 followers
-
-
Hydra Obfuscator (Modded) About File: .NET Framework 4.8, 32-bit preferred Used Obfuscator: Hydra modded Used Features: JIT Obfuscation, JIT fornicationer, String Encryption (XOR), Control Flow, Proxy Class, Renamer, L2F, INT Encode, Method to delegate, Anti Decompiler & Tamper & Dump & Proxy, Cctor hider. Difficulty: 6/10 Goal: Crack and deobfuscate it competely. (u can ignore renamer) File Information Submitter whystarlix Submitted 03/05/2026 Category UnPackMe (.NET) View File
-
- 0 replies
- 888 views
- 1 follower
-
-
Safengine Licensor v2.4 (HWID Lock) I coded a simple Win x64 GUI application with a close button and protected it using Safengine Shielden v2.4. Challenge is to; bypass the hardware ID lock; unpack the application. Let us go together to solve this issue. File Information Submitter lovejoy226 Submitted 06/11/2024 Category UnPackMe View File
-
-
- 30 replies
- 59.7k views
- 2 followers
-
-
ConsoleApp6_packed.exe A basic .NET loader stub used as a learning project. Goal: unpack and extract the real .NET app. File Information Submitter modz50 Submitted 02/18/2026 Category UnPackMe View File
-
WinLicense v3.2.2 (Window Function Through an External Plugin) This is a WinLicense 3.2.2/sample, set by default, without adding an SDK in the source code, only adding a window function through an external plugin. I don't know if bypass can be cracked, I tested it and it doesn't. Shedding may be more complicated.Please use your own way to crack it. Whether it's molting, bypass, or keygen, they are all the best methods. No need to upload your proposal, posting a picture is the best answer. I will strive to learn towards your achievements. HWID：1031-E184-1D1E-92A8-AA82-151F-E2BC-34EE NAME：Mr.Leng .RegistCode:2FGP7NTY-22AMY4QL-XXEHAOKD-ZJKHKDKR-VY66SHXY-YTEQXVBF-GAXAEFIA-…
-
-
- 19 replies
- 12.2k views
- 2 followers
-
-
Now I am enough to solve it... Thanks all tsrh.team.trial.keygenme.1.zip
-
Difficulty : (3-4 Maybe?) Language : (C# .NET) Platform : (Windows) OS Version : (Windows 10) Packer / Protector : (FujiFuscator) Description : Please give me a detailed tutorial on how you unpacked this. Screenshot : UnPackMe.exe
-
-
- 18 replies
- 27.3k views
- 1 follower
-
-
TinyCrackMe - WinLicense 3.1.7.0 Edition === SPOILER INSIDE SOURCE CODE TAB === A WinLicense'd version of TinyCrackMe Rules: 1. Unpack first 2. Do whatever you want after unpack, as long as ":3" MessageBox appear :3 Just want to see how long ppl will crack the latest version of WinLicense... WL Protection: - Anti-Debugger - Advanced API-Warping - Compress And Encrypt (all 3 options) - Full Encrypt Strings - Detect File/Registry Monitor - Entry Point Virt - Anti File Patching - Perform Protection Check - VMware/Virtual PC Allowed WLVM: - SHARK32 (Black, Red) - PUMA32 (Black, Red) - EAGLE32 (Black) Happy reversing :3 …
-
-
- 33 replies
- 26.4k views
- 2 followers
-
-
Prometheus (12 Layers of Insanity) A recruitment challenge for those who see what others cannot. The binary guards an encrypted message. To reveal it, you must provide the correct 28-character key. There is no backdoor, no shortcut, no unintended solution—only the key. The verification process spans twelve interconnected layers. Each depends on others. Disrupting one cascades through all. The binary knows its own shape and will notice if you change it. Some defenses are apparent through static analysis. Others manifest only at runtime. A few exist in the liminal space between instruction and execution—observable only through their effects, never their implementation. Di…
-
-
- 6 replies
- 6.1k views
- 1 follower
-
