Microsoft has released seven items in their Security Bulletin for March 2013. Most are for Microsoft Office, one is for Internet Explorer and two in Windows itself.
NOTE: If you are using Windows 8, in addition to the other Microsoft Windows, Internet Explorer and Microsoft Office updates, you will also get a Flash update. Don’t forget that Flash is built into Internet Explorer in Windows 8, just like Flash is included with and updated by Google Chrome. What that means is that you do not have to keep Flash updated for those two browsers – IE 10 in Windows 8 and Google Chrome keep Flash updated for you.
More information at Security Garden blog.
You do still need to keep Flash updated for other browsers like Firefox and Opera, and Internet Explorer on earlier versions of Windows.