Frontend Content Forms for User Submissions (UGC) < 2.8.16 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'buddyforms_nav' Shortcode

Description

The Post Form – Registration Form – Profile Form for User Profiles – Frontend Content Forms for User Submissions (UGC) plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'buddyforms_nav' shortcode in all versions up to, and including, 2.8.15 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.