DSA-4401-1

In WordPress before 4.9.9 and 5.x before 5.0.1, authors could modify metadata to bypass intended restrictions on deleting files.

In WordPress before 4.9.9 and 5.x before 5.0.1, contributors could conduct PHP object injection attacks via crafted metadata in a wp.getMediaItem XMLRPC call. This is caused by mishandling of serialized data at phar:// URLs in the wp_get_attachment_thumb_file function in wp-includes/post.php.

In WordPress before 4.9.9 and 5.x before 5.0.1, when the Apache HTTP Server is used, authors could upload crafted files that bypass intended MIME type restrictions, leading to XSS, as demonstrated by a .jpg file without JPEG data.

In WordPress before 4.9.9 and 5.x before 5.0.1, crafted URLs could trigger XSS for certain use cases involving plugins.

In WordPress before 4.9.9 and 5.x before 5.0.1, the user-activation page could be read by a search engine's web crawler if an unusual configuration were chosen. The search engine could then index and display a user's e-mail address and (rarely) the password that was generated by default.

In WordPress before 4.9.9 and 5.x before 5.0.1, authors could bypass intended restrictions on post types via crafted input.

In WordPress before 4.9.9 and 5.x before 5.0.1, contributors could modify new comments made by users with greater privileges, possibly causing XSS.

WordPress before 4.9.9 and 5.x before 5.0.1 allows remote code execution because an _wp_attached_file Post Meta entry can be changed to an arbitrary string, such as one ending with a .jpg?file.php substring. An attacker with author privileges can execute arbitrary code by uploading a crafted image containing PHP code in the Exif metadata. Exploitation can leverage CVE-2019-8943.