WP-Members Membership Plugin <= 3.5.4.3 - Authenticated (Subscriber+) Stored Cross-Site Scripting via Multiple Checkbox and Multiple Select User Profile Fields

The WP-Members Membership Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the Multiple Checkbox and Multiple Select user profile fields in all versions up to, and including, 3.5.4.3 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.