CVE-2026-3596: Riaxe Product Customizer <= 2.1.2 - Missing Authorization to Unauthenticated Arbitrary Options Update to Privilege Escalation via 'install-imprint' AJAX Action

The Riaxe Product Customizer plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 2.1.2. The plugin registers an unauthenticated AJAX action ('wp_ajax_nopriv_install-imprint') that maps to the ink_pd_add_option() function. This function reads 'option' and 'opt_value' from $_POST, then calls delete_option() followed by add_option() using these attacker-controlled values without any nonce verification, capability checks, or option name allowlist. This makes it possible for unauthenticated attackers to update arbitrary WordPress options, which can be leveraged for privilege escalation by enabling user registration and setting the default user role to administrator.