The latest Mac malware to be discovered is called OSX.ZuRu. It spreads via infected apps from sponsored search results.
The legitimate and the malicious iTerm2 application bundles contain a massive number of files, including several Mach-O binaries. Moreover, the malicious version appears largely benign (as is the case with most applications that have been surreptitiously trojanized). As such, it takes us a minute to uncover the malicious component.