The Waiting: One-click countdowns plugin for WordPress is vulnerable to authorization bypass due to a missing capability check on 'saveLang' functions in versions up to, and including, 0.6.2. This could lead to Cross-Site Scripting due to insufficient input sanitization and output escaping. This makes it possible for subscriber-level attackers to access functions to save plugin data that can potentially lead to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.