Smart App Banners <= 1.2 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'size' and 'verticalalign' Shortcode Attributes

The Smart App Banners plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'size' and 'verticalalign' parameters of the 'app-store-download' shortcode in all versions up to, and including, 1.2 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.