If you haven’t updated your Mac today you will notice there is an update waiting in your app store for you to update the stability and security of Safari. The OS X security updates for the safari web browser revolve around fixes for the webkit by updating any vulnerability. Multiple memory corruption issues existed in the WebKit these issues were tackled through improved memory handling. This will impact when visiting a maliciously crafted website that could lead to an unexpected application termination or arbitrary code execution. A user interface inconsistency existed in Safari that allowed an invader to misrepresent the URL. This issue was also investigated and improved the user interface consistency checks preventing users from discerning a phishing attack.
So if you are a Safari user you might want to update your Mac with this to insure that your security is secure.