The Timeline Widget For Elementor (Elementor Timeline, Vertical & Horizontal Timeline) plugin for WordPress is vulnerable to Stored Cross-Site Scripting via image URLs in the plugin's timeline widget in all versions up to, and including, 1.5.3 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers with contributor-level and above permissions to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page, changes the slideshow type, and then changes it back to an image.