EmbedPress <= 4.6.5 - Reflected Cross-Site Scripting via 'hash' and 'unique' Parameters

The EmbedPress – PDF Embedder, 3D PDF FlipBook, Google Reviews, YouTube Videos, Upload & Embed PDF documents plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'unique' parameter in all versions up to, and including, 4.6.5 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. This is a regression: the esc_url() wrapper that remediated the equivalent CVE-2023-5749 in version 3.9.2 was removed in version 4.3.0 during a refactor that introduced the 'unique' parameter.