20% of all Macs Carrying Windows Malware, Says Sophos

Apple users have generally eschewed anti-malware software and safe online practices, because “Macs don’t get viruses”. We’ve learned that’s a fallacy, of course, and Mac users would be wise to heed some advice about malware safety, but Sophos found that Macs were actually more likely to spread malware than be infected by it.

In a blog post that veered sharply and irretrievably into disturbing comparisons between computer malware and Chlamydia, security firm Sophos announced a study that found that of the 100,000 computers they surveyed (that were equipped with Sophos software), one in five had some kind of Windows malware lurking onboard.


(Yes, Sophos can benefit from making people scramble to buy security software. Yes, Sophos actually links to its own anti-malware software in the post announcing the findings. No, you should not disregard the findings or what they portend.)

Note well that Windows malware can’t do much to a Mac, but that doesn’t mean Mac users can’t be carriers for the stuff; all it takes is sharing a flash drive, sending an email attachment--any typical computer-to-computer communication, really.

Additionally, Sophos found that one in thirty-six (2.7%) Macs actually had Mac OS X-specific malware on board. Yep, the number of infected Macs is ten times smaller than the number of Macs carrying an infection.

Armed with that information, Mac users should take heed, be a good neighbor, and take precautions against malware. (No, it doesn’t have to be something made by Sophos. Nobody’s endorsing anybody here.)