If you use Google's Chrome browser on Windows, Mac and Linux, update it now. Google has issued patches for 12 "high" and "medium" severity security flaws for Chrome.
The vulnerabilities were found as part of Google's bug bounty program which paid out US$70,000 to security researchers that found a total of 26 bugs.
You can find the full list of vulnerabilities here. Google is encouraging users to update to Chrome 55 (specifically Chrome 55.0.2883.75) which contains all the fixes for the security bugs.
Chrome 55 also automatically blocks Adoble Flash content, in favour of HTML5.