Post Duplicator <= 3.0.8 - Missing Authorization to Authenticated (Contributor+) Protected Post Meta Insertion via 'customMetaData' Parameter

The Post Duplicator plugin for WordPress is vulnerable to unauthorized arbitrary protected post meta insertion in all versions up to, and including, 3.0.8. This is due to the `duplicate_post()` function in `includes/api.php` using `$wpdb->insert()` directly to the `wp_postmeta` table instead of WordPress's standard `add_post_meta()` function, which would call `is_protected_meta()` to prevent lower-privileged users from setting protected meta keys (those starting with `_`). This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary protected post meta keys such as `_wp_page_template`, `_wp_attached_file`, and other sensitive meta keys on duplicated posts via the `customMetaData` JSON array parameter in the `/wp-json/post-duplicator/v1/duplicate-post` REST API endpoint.

Because it turns on account access, WordSec's login security is the relevant layer: role-based two-factor, captcha and brute-force limits raise the cost of getting the account this needs. None of that substitutes for the fix: Post Duplicator 3.0.9 closes this, and updating the plugin is the step that ends it.

• Login Security
• Alerts