The Newsletter2Go plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the 'resetStyles' AJAX action in all versions up to, and including, 4.0.14. This makes it possible for authenticated attackers, with Subscriber-level access and above, to reset styles.

The Newsletter2Go plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘style’ parameter in all versions up to, and including, 4.0.13 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.