The Media Library Assistant plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'mla_gallery' shortcode in versions up to, and including, 3.10 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.
https://plugins.trac.wordpress.org/changeset/2963256/media-library-assistant