Jetpack 13.0 - 14.0 - Reflected DOM-based Cross-Site Scripting

The Jetpack – WP Security, Backup, Speed, & Growth plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via 'postmessage' in versions 13.0 to 14.0 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. The issue only affects websites hosted on WordPress.com.