WordPress Update 4.2.2 - Security Alert - 5/7/15

Why was this update released?

This security release addresses two major issues. WordPress states the following:

• "The Genericons icon font package, which is used in a number of popular themes and plugins, contained an HTML file vulnerable to a cross-site scripting attack. All affected themes and plugins hosted on WordPress.org (including the Twenty Fifteen default theme) have been updated today by the WordPress security team to address this issue by removing this nonessential file. To help protect other Genericons usage, WordPress 4.2.2 proactively scans the wp-content directory for this HTML file and removes it. Reported by Robert Abela of Netsparker."
• "WordPress versions 4.2 and earlier are affected by a critical cross-site scripting vulnerability, which could enable anonymous users to compromise a site. WordPress 4.2.2 includes a comprehensive fix for this issue. Reported separately by Rice Adu and Tong Shi."

"The release also includes hardening for a potential cross-site scripting vulnerability when using the visual editor. This issue was reported by Mahadev Subedi."

You can read the official announcement at the WordPress.org site.

What should I do?

WordPress strongly encourages you to update your sites immediately.