README.md

RunPE

C# reflective loader for unmanaged binaries.

Usage

Usage: RunPE.exe <file-to-run> <args-to-file-to-run>
        e.g. RunPE.exe C:\Windows\System32\net.exe localgroup administrators

Alternative usage: RunPE.exe ---f <file-to-pretend-to-be> ---b <base64 blob of file bytes> ---a <base64 blob of args>
        e.g: RunPE.exe ---f C:\Windows\System32\svchost.exe ---b <net.exe, base64 encoded> ---a <localgroup administrators, base64 encoded>

Build configuration options

Edit the compilation symbols to quickly adjust the program flow: (Right click the project in Visual Studio -> Properties -> Build -> Conditional Compilation Symbols)

• DEBUG (automatically added in Debug release mode) -> Very verbose logging
• BREAK_TO_ATTACH -> Print "Press Enter to continue..." and await input so can attach debugger

PE Compilation Limitations

Executables launched by RunPE must be statically linked in order for StdOut and StdErr redirection to work correctly. To change this setting in Visual Studio:

• Open the project's properties
• Navigate to Configuration Properties -> C/C++ -> Code Generation
• Change the value of Runtime Library to either Multi-threaded (/MT) or Multi-threaded Debug (/MTd)
• Recompile the project

Argument Limitiations

Executables that do not use the Window's API CommandLineToArgvW in order to parse arguments will not be passed appropriately through RunPE. When running PE's that the operator has control over compilation, it is suggested to add support for parsing arguments using this API.

For example, the following code will work when the program is run independently, but will fail when passed to RunPE since "foo" has been shifted to argv[2]:

if (argv[1] == "foo") {
    bar();
}

Example for refactoring argv to CommandLineArgvW:

#include <stdio.h>
#include <Windows.h>

int main(int argc, char* argv[]) {
	int nArgs;
	LPWSTR *szArglist;
	
	szArglist = CommandLineToArgvW(GetCommandLineW(), &nArgs);

	for (int i = 0; i < nArgs; i++) {
		printf("argv[%d]: %ws\n", i, szArglist[i]);
	}

	return 0;
}