CVE-2026-17553 [HIGH] – The WP EasyCart plugin for WordPress is vulnerable to privilege escalation in versions up

The WP EasyCart plugin for WordPress is vulnerable to privilege escalation in versions up to, and including, 5.9.3. This is due to the ec_ajax_save_page_default_options() AJAX handler iterating over every $_POST key and passing it directly into update_option() without any allowlist, while gating the handler only on ‘manage_options’ OR the plugin’s custom ‘wpec_manager’ capability. The plugin’s built-in ‘wpec_store_manager’ role holds ‘wpec_manager’ but not ‘manage_options’, and the required nonce is emitted on frontend product/category templates that render for any user with ‘wpec_manager’. This makes it possible for authenticated attackers, with Store Manager-level access and above, to elevate their privileges to administrator by updating arbitrary WordPress options such as default_role=’administrator’ and users_can_register=’1′, then self-registering a new account that is assigned the administrator role.