Adobe Flash Player 21.0.197 and earlier versions for Windows, Macintosh, Linux, Chrome OS and Chrome OS will be issued an emergency security update. The vulnerability has been given a critical severity rating by Adobe. Users are advised to update their systems at the earliest opportunity to avoid exploitation of the vulnerability. If youre not quite ready to take the step of entirely uninstalling Flash, then you should at the very least consider enabling Click to Play which stops Flash elements from being rendered in your browser unless you give specific permission.”]
Source: https://grahamcluley.com/emergency-adobe-flash-update-prepped-hackers-actively-exploit-flaw/