Malware that targets Mac OS X isn t catching up to Windows-based malware in terms of volume and variety, but it seems that OS X malware may be adopting some of the more successful tactics that Windows viruses have been using to trick users. The new piece of malware hides inside a PDF file and delivers a backdoor that hides on the user s machine once the malicious file is opened. The Trojan then installs the backdoor, which is named Imuler.A, which attempts to communicate with a command-and-control server.
Source: https://threatpost.com/new-mac-os-x-trojan-imuler-hides-inside-malicious-pdf-092311/75682/