oscommerce v2.3.4.1 has a functional problem in user registration and password rechecking, where a non-identical password can bypass the checks in /catalog/admin/administrators.php and /catalog/passwordreset.php

osCommerce 2.3.4.1 has an incomplete '.htaccess' for blacklist filtering in the "product" page. Remote authenticated administrators can upload new '.htaccess' files (e.g., omitting .php) and subsequently achieve arbitrary PHP code execution via a /catalog/admin/categories.php?cPath=&action=newproduct URI.

osCommerce 2.3.4.1 has an incomplete '.htaccess' for blacklist filtering in the "product" page. Because of this filter, script files with certain PHP-related extensions (such as .phtml and .php5) didn't execute in the application. But this filter didn't prevent the '.pht' extension. Thus, remote authenticated administrators can upload '.pht' files for arbitrary PHP code execution via a /catalog/admin/categories.php?cPath=&action=newproduct URI.

osCommerce 2.3.4.1 has XSS vulnerability via the authenticated user entering the XSS payload into the title section of newsletters.