The Radio Player – Live Shoutcast, Icecast and Any Audio Stream Player for WordPress plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'align' attribute within the 'wp:radio-player' Gutenberg block in all versions up to, and including, 2.0.78 due to insufficient input sanitization and output escaping. 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.