The most reliable way to convert an existing EXE is to use a "loader-in-shellcode" tool. These tools prepend a small, specialized loader (a "stub") to your executable that mimics the Windows OS loader's behavior at runtime.
Writing this loader from scratch is tedious. Fortunately, the security community has developed tools to automate this process.
Several tools exist for this purpose, ranging from simple scripts to sophisticated loaders. 1. Donut (Most Popular)
: Use the Process Environment Block (PEB) to locate kernel32.dll in memory.
The converter parses the portable executable (PE) structure to understand where code sections ( .text ) and data sections ( .data ) reside. convert exe to shellcode
Donut does not actually convert the machine code inside your EXE to be position-independent. Instead, it creates a highly optimized, position-independent and appends your original EXE payload (often encrypted) to it. When the Donut payload is executed in memory:
Raw shellcode must be . It cannot rely on fixed memory addresses or pre-resolved Import Address Tables (IAT) to find APIs like MessageBoxA or VirtualAlloc .
int main() unsigned char shellcode[] = /* paste payload.bin bytes here */ ;
Donut generates a payload that decrypts and loads your EXE directly into memory using a highly optimized loader stub. Command Example: donut.exe -i my_executable.exe -o payload.bin -a 2 Use code with caution. (The -a 2 flag specifies an x64 architecture payload). 2. Pe2shc (By Hasherazade) The most reliable way to convert an existing
Converting an EXE to shellcode is not magic. You will encounter issues:
A standard Windows EXE is formatted as a Portable Executable (PE) file. It contains structures that do not exist in raw shellcode:
The most reliable way to create shellcode from executable logic is to write the program in C or C++ while adhering to strict position-independent constraints, then extracting the compiled bytes. To write PIC in C, you must:
Allows running an entire application entirely in memory, avoiding disk I/O, which reduces the chance of detection by antivirus (AV) or Endpoint Detection and Response (EDR) solutions. Fortunately, the security community has developed tools to
It appends a custom loader to the front of the PE file. The entry point of the shellcode jumps to this loader, which redirects the execution flow, maps the PE sections, and handles relocations. Basic command line usage: pe2shc.exe target_program.exe payload.bin Use code with caution.
This feature can be useful for security professionals, researchers, and developers who need to work with shellcode for various purposes. However, it's essential to ensure that the converter is used responsibly and in compliance with applicable laws and regulations.
The converter adds a small piece of assembly code (a "stub") that acts as a reflective loader.
Effective shellcode must satisfy several technical constraints: