When uploading an image file to a bulletin board developed with XpressEngine, a vulnerability in which an arbitrary file can be uploaded due to insufficient verification of the file. A remote attacker can use this vulnerability to execute arbitrary code on the server where the bulletin board is running.

In XE 1.116, when uploading the Normal button, there is no restriction on the file suffix, which leads to any file uploading to the files directory. Since .htaccess only restricts the PHP type, uploading HTML-type files leads to stored XSS vulnerabilities. If the .htaccess configuration is improper, for example before the XE 1.11.2 version, you can upload the PHP type file to GETSHELL.

XE before 1.11.6 is vulnerable to Unrestricted file upload via modules/menu/menu.admin.controller.php. When uploading the Mouse over button and When selected button, there is no restriction on the file suffix, which leads to any file uploading to the files directory. Since .htaccess only restricts the PHP type, uploading HTML-type files leads to stored XSS vulnerabilities.