Reservation.Studio widget <= 1.0.11 - Authenticated (Administrator+) Stored Cross-Site Scripting

The Reservation.Studio widget plugin for WordPress is vulnerable to Stored Cross-Site Scripting via admin settings in versions up to, and including, 1.0.11 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only impacts multi-site installations and installations where unfiltered_html has been disabled. Note: This vulnerability is partially patched in versions 1.0.8 and above.