WordPress announced today a security and maintenance release to version 4.2.4. This release fixes a number of vulnerabilities uncovered by WordPress security experts.
From WordPress.org WordPress 4.2.4 Security and Maintenance release.:
This release addresses six issues, including three cross-site scripting vulnerabilities and a potential SQL injection that could be used to compromise a site, which were discovered by Marc-Alexandre Montpas of Sucuri, Helen Hou-Sandí of the WordPress security team, Netanel Rubin of Check Point, and Ivan Grigorov. It also includes a fix for a potential timing side-channel attack, discovered by Johannes Schmitt of Scrutinizer, and prevents an attacker from locking a post from being edited, discovered by Mohamed A. Baset.
Please update your WordPress sites immediately. Download WordPress 4.2.4 or click “Update” in your Dashboard admin panel. Always backup before upgrading.
WordPress 4.2.4 also fixes four bugs. View the release notes or consult the list of changes.