Smart Slider 3 < 3.5.1.39 - Contributor+ Stored XSS via 'slider' Block Attribute

Description

The plugin is vulnerable to Stored Cross-Site Scripting via the 'slider' Block Attribute, due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The injected scripts execute specifically when a user opens the affected post in the WordPress block editor, making Editors and Administrators the primary targets.