A new piece of malware which disguises itself as a PDF download and could give hackers remote access to a computer has been discovered as a potential threat to Mac users.

The trojan, identified as Trojan-Dropper:OSX/Revir.A, opens a botnet backdoor by tricking the user into downloading and opening a Chinese language PDF file while it installs itself in the background, according to security researchers at F-Secure.



Trojans typically mask themselves as a PDF （pdf related: pdf converter）and infect systems while the user is busy opening the file. But researchers believe that this particular sample may be stealthier than usual malware.

The new trojan differs from most Windows PDF malware in that it arrived to researchers without the usual "pdf.exe" extension or icon(pdf tips: pdf to dwg). Researchers note that because extension and icon data are stored and displayed differently on Macs, this sample could be more difficult to detect than Windows counterparts, as it can adopt any extension desired.

The technique of using a PDF file as a ruse for the propagation of malware has been a mainly Windows problem in the past, remaining a minimal threat to Mac users.