Premium Portfolio Features for Phlox theme <= 2.3.4 - Authenticated (Contributor+) Stored Cross-Site Scripting

The Premium Portfolio Features for Phlox theme plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'aux_recent_portfolios_grid' shortcode in all versions up to, and including, 2.3.4 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers with contributor-level and above permissions to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.