The Genzel breadcrumbs plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 1.2. This is due to missing or incorrect nonce validation on the _options_page function. This makes it possible for unauthenticated attackers to update the plugin's breadcrumb configuration, including templates, delimiter, home label, home URI, and breadcrumb rules via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.