LatePoint < 5.4.0 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode Attributes

Description

The LatePoint plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'btn_wrapper_classes' attribute of the 'latepoint_resources' shortcode in all versions up to, and including, 5.3.2. This is due to insufficient input sanitization and output escaping in the 'locations' branch of the 'shortcode_latepoint_resources' function. 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.