Post Duplicator vulnerabilities

The Post Duplicator plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the `duplicate_post()` function in all versions up to, and including, 3.0.11. This is due to the function not verifying that the user has `edit_others_posts` capability before accepting a `selectedAuthorId` parameter via the `duplicate-post` REST endpoint. This makes it possible for authenticated attackers, with Contributor-level access and above, to create duplicated posts attributed to any user, including administrators.

The Post Duplicator plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 3.0.11. This is due to the `duplicate_post_permissions()` permission callback only verifying the `duplicate_posts` capability without checking whether the requesting user holds `publish_posts` or other status-gated capabilities. This makes it possible for authenticated attackers, with Contributor-level access and above, to create duplicate posts with `future` (scheduled, auto-publishes) or `private` status, bypassing editorial review. Additionally, the REST endpoint does not enforce administrator-configured post-type duplication restrictions, allowing duplication of post types that have been explicitly disabled.

Post Duplicator versions up to 3.0.10 are vulnerable to PHP Object Injection, which may lead to unauthorized access or data manipulation.