Easy Testimonials <= 3.9.5 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode

The Easy Testimonials plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'testimonials_grid ' shortcode in all versions up to, and including, 3.9.5 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.