Slim SEO < 4.5.4 - Authenticated (Contributor+) Stored Cross-Site Scripting via slim_seo_breadcrumbs Shortcode

Description

The Slim SEO – Fast & Automated WordPress SEO Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's slim_seo_breadcrumbs shortcode in all versions up to, and including, 4.5.3 due to insufficient input sanitization and output escaping on user supplied attributes. 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.