WordPress 4.5.3 is now available. This is a security release for all previous versions and we strongly encourage you to update your sites immediately.
WordPress versions 4.5.2 and earlier are affected by several security issues: redirect bypass in the customizer, reported by Yassine Aboukir; two different XSS problems via attachment names, reported by Jouko Pynnönen and Divyesh Prajapati; revision history information disclosure, reported independently by John Blackbourn from the WordPress security team and by Dan Moen from the Wordfence Research Team; oEmbed denial of service reported by Jennifer Dodd from Automattic; unauthorized category removal from a post, reported by David Herrera from Alley Interactive; password change via stolen cookie, reported by Michael Adams from the WordPress security team; and some less secure sanitize_file_name edge cases reported by Peter Westwood of the WordPress security team.
Thank you to the reporters for practicing responsible disclosure.
Download WordPress 4.5.3 or venture over to Dashboard → Updates and simply click “Update Now.” Sites that support automatic background updates are already beginning to update to WordPress 4.5.3.
Thanks to everyone who contributed to 4.5.3:
Boone Gorges, Silvan Hagen, vortfu, Eric Andrew Lewis, Nikolay Bachiyski, Michael Adams, Jeremy Felt, Dominik Schilling, Weston Ruter, Dion Hulse, Rachel Baker, Alex Concha, Jennifer M. Dodd, Brandon Kraft, Gary Pendergast, Ella Iseulde Van Dorpe, Joe McGill, Pascal Birchler, Sergey Biryukov, David Herrera and Adam Silverstein.
WordPress 4.5.2 is now available. This is a security release for all previous versions and we strongly encourage you to update your sites immediately.
WordPress versions 4.5.1 and earlier are affected by a SOME vulnerability through Plupload, the third-party library WordPress uses for uploading files. WordPress versions 4.2 through 4.5.1 are vulnerable to reflected XSS using specially crafted URIs through MediaElement.js, the third-party library used for media players. MediaElement.js and Plupload have also released updates fixing these issues.
Both issues were analyzed and reported by Mario Heiderich, Masato Kinugawa, and Filedescriptor from Cure53. Thanks to the team for practicing responsible disclosure, and to the Plupload and MediaElement.js teams for working closely with us to coördinate and fix these issues.
Download WordPress 4.5.2 or venture over to Dashboard → Updates and simply click “Update Now.” Sites that support automatic background updates are already beginning to update to WordPress 4.5.2.
Additionally, there are multiple widely publicized vulnerabilities in the ImageMagick image processing library, which is used by a number of hosts and is supported in WordPress. For our current response to these issues, see this post on the core development blog.