Security researchers at Sophos and F-Secure have uncovered a new Mac Trojan that masquerades as a PDF file.

"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," writes Threatpost's Dennis Fisher. "Once the user executes the malware, it puts the malicious PDF on the user's machine and then opens it as a way to hide the malicious activity that's going on in the background, according to an analysis by researchers at F-Secure."

"The Trojan then installs the backdoor, which is named Imuler.A, which attempts to communicate with a command-and-control server," Fisher writes.

Go to "New Mac OS X Trojan Imuler Hides Inside Malicious PDF" to read the details.

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