The Revival & Heartbleed
A few days ago a bug was found in some common infrastructure used throughout the internet which meant that more or less no site was secure to the bug. It is known as the Heartbleed bug. (further simplified details via BBC News)
An attacker aware of the bug could more or less hack anything on the net including government/tax portals and all banks to social networks to email providers to shopping sites. From the BBC News link:
Security expert Brue Schneier described it as "catastrophic". "On the scale of one to 10, this is an 11."