arbitrary file upload vulnerability found in GetSimple CMS by abusing

GetSimpleCMS suffers from arbitrary file upload vulnerability which allows a malicious authenticated user to upload an arbitrary file which results in arbitrary code execution.

The main reason of this vulnerability is the the application uses a blacklist technique to compare  the mime type and the extension of the uploaded file against predefined mime types and extensions.

If the mime type and the extension of the uploaded file is not in the blacklist arrays , the application will upload it.

the vulnerable code is in "security_functions.php" page under "admin/inc" folder.