Podlove Podcast Publisher <= 4.2.2 - Cross-Site Request Forgery via ajax_transcript_delete Function

The Podlove Podcast Publisher plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 4.2.2. This is due to missing or incorrect nonce validation on the ajax_transcript_delete() function. This makes it possible for unauthenticated attackers to delete arbitrary episode transcripts via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.