CVE-2024-13883

The WPUpper Share Buttons plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 3.51. This is due to missing or incorrect nonce validation on the ‘save_custom_css_request’ function. This makes it possible for unauthenticated attackers to inject custom CSS to modify a site via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

More information : https://plugins.trac.wordpress.org/browser/wpupper-share-buttons/trunk/Controller/ajax.controller.php#L94