using System.Runtime.InteropServices;

internal class Program
{
    internal static uint MEM_COMMIT = 0x1000;
    internal static uint PAGE_EXECUTE_READWRITE = 0x40;

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

    internal delegate int BytesLauncher();

    static void Main()
    {
        byte[] rawBytes = [ 0x90, 0x90, 0xC3 ];

        var payload = VirtualAlloc(IntPtr.Zero, rawBytes.Length, MEM_COMMIT, PAGE_EXECUTE_READWRITE);

        Marshal.Copy(rawBytes, 0, payload, rawBytes.Length);

        if (Marshal.GetDelegateForFunctionPointer(
            payload, typeof(BytesLauncher)) is BytesLauncher ExecutePayload)
        {
            _ = ExecutePayload();
        }
    }
}