How save is it to use in its current status?
Our recommendation is to always use the latest version of Flash Player, and to enable automatic updates. Using a 64-bit browser with a plug-in sandbox on a modern operating system also have significant bearing on the difficulty for an attacker to compromise a system.
Security is a key engineering priority for us, and the Flash Player engineering team is engaged in a proactive and continuous program of hardening Flash Player against emerging threats, in collaboration with partners like Microsoft and Google, who provide expert advice and specialized tools, techniques and resources. Because we're continuously improving Flash Player,
When creating new work, we utilize a Secure Development Lifecycle, which includes things like peer-review, and code and design reviews utilizing both internal and external consultants, as well as extensive testing and test review.
When things do go wrong, the Adobe Product Security Incident Response Team is available to respond to any incoming security reports 24/7/365, and we work diligently to address both responsibly disclosed issues and issues discovered in the wild.
You can also subscribe to the Adobe Security Notification Service to get real-time announcements, and look at past and current security bulletins and advisories here: Adobe Security Bulletins and Advisories
Hope that helps!