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

Am I affected?

• Check your version: in wp-admin go to Plugins → Installed Plugins and read the version under Post Duplicator.
• No admin access? Run a passive check of your site. It reads public files only.

What to do

1. Update to version 3.0.9, or a newer patched version
2. Rotate administrator passwords and application secrets if the site ran a vulnerable version while publicly reachable.
3. Watch Post Duplicator to get an email when the next vulnerability is published.

Advisory

Source description from Wordfence Intelligence, credited to bashu.

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.

Exploits & references

Proof-of-concept & detection

No public proof-of-concept or detection template is known for this vulnerability.

Advisories & patches

• Advisorywordfence.com

Related CVEs

Timeline

1. Feb 24, 2026

   CVE published

   Severity medium, CVSS 4.3

2. Nov 13, 2026

   Record last updated