Infosec: One In Five Macs Is Infected With Windows Malware

One in thirty-six Macs harbours OS X-specific malware while one in five features at least one Windows virus or Trojan

Researchers at security firm Sophos have discovered that one in five Macs is infected with Windows malware, while one in thirty-six contains a Mac OS X-specific virus.

The study, which looked at 100,000 Macs over a seven day period, found that the most common malware to afflict the OS specifically was the Flashback Trojan, which at one point infected more than 600,000 systems around the world.

Easy target

Graham Cluley, Sophos’ senior technology consultant, notes in the Naked Security blog that despite being seven times more prevalent, Windows malware is not usual in Macs unless users also run Windows on their system. However, Macs will continue to serve as a transmission vector for viruses and Trojans so long as anti-malware software is not installed.

Cluley adds that while the spread of malware to and from Macs is no different than that for Windows computers, a lack of anti-virus implementation means that it sticks around for longer. Some samples collected by Sophos found malware dating back to 2007.

“Sadly, cybercriminals view Macs as a soft target, because their owners are less likely to be running anti-virus software,” he wrote. “Bad guys may also believe that Mac users are likely to have a higher level of disposable income than the typical Windows user. So, they might believe the potential for return is much higher.”

“What Mac users really need to do is protect their computers now or risk allowing the malware problem on Macs to become as big as the problem on PCs in the future.”

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