WordPress has release security update for all previous versions and encourages you to update your sites immediately.

Also Joomla has released new version 3.8 including some security fixes.

Magento released updates for Magento Commerce and Open Source 2.1.9 and 2.0.16 that fixed numerous flaws, including a critical remote code execution vulnerability. The remote code execution flaw impacts content management system (CMS) and layouts, it could be exploited by an administrator with limited privileges to add malicious code when creating a new CMS page