You get a email saying that there is a package waiting for you "undelivered courier item" and you need to download a PDF. Do not do this it will not ask for your permission to install it.
OSX/LaoShu-A.
"LaoShu-A as good as hands control of your Mac over to the attackers
Read this story for complete info.
http://www.gmanetwork.com/news/story/344885/scitech/technology/mac-users-warned-vs-new-trojan-malware
