Released on December 5th, the latest Flash addresses two security vulnerabilities in earlier versions. The security bulletin for Flash 18.104.22.168 provides additional details.
If you’re still using Flash, you should install the new version as soon as possible. If you use a web browser with a Flash plugin enabled, don’t wait: update now. If you’re not sure whether your browser has Flash enabled, visit the Flash Player Help page with that browser. The Help page will detect Flash in your browser, tell you which version is installed, and provide a download link for the latest version.
Web browsers that include their own embedded Flash will be updated via their usual channels: for Microsoft browsers, that means Windows Update. Chrome usually updates itself automatically, but you can trigger an update by navigating its menu to
About Google Chrome.