bbp style pack <= 5.6.7 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode

The bbp style pack plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'display-top-users' shortcode in versions up to, and including, 5.6.7 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level permissions and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.