The plugin does not validate and escape some of its shortcode attributes before outputting them back in the page, which could allow users with a role as low as contributor to perform Stored Cross-Site Scripting attacks which could be used against high privilege users such as admins.
1. Create a Podcast episode.
2. Insert the following shortcode in a page/post: [podcast_playlist style='" onmouseover="alert(1)"']
3. Hover over the player, and the alert triggers successfully.