Microsoft Security Intelligence Report provides summarized information from the last 10 years focusing on software vulnerabilities, software vulnerability exploits, malicious, and potentially unwanted software. The report discusses the origin of malware following it through the decade of mutation all the way upto cloud. However, the report does not cover specific threats to cloud in detail at this point.
Brief introductions to threat families ranging from Win32/Nimda to Win32/Bagle, Win32/Conficker, JS/Pornpop(of specially crafted JavaScript-enabled objects that attempt to display pop-under advertisements) and Win32/OpenCandy are provided. This report makes a good executive summary of software threats and trends they follow. It can be downloaded from here.
