February has been a bad month for both Windows PC and Server users, as well as iPhone and iPad ones, when it comes to security vulnerabilities. Specifically, zero-day vulnerabilities that were already being exploited before the security updates to fix them were made available. Now the U.S. Cybersecurity and Infrastructure Security Agency (CISA) has stepped in by adding the three Microsoft and one Apple zero-day security issues to the ‘Known Exploited Vulnerabilities Catalog.’