Absence of OS X malware baffles security experts

While malware - viruses, spyware and the like - is widespread on Windows machines, not one pervasive infection has been witnessed in the six years since OS X 10.0 was released. This surprises the security industry despite a whole month being devoted to finding exploits in the operating system.

And that cannot simply be put down to the fact that OS X runs on a variant of BSD Unix: there are 700 known malware items for other Unix and Linux distributions.

"OS X is originally based on BSD," Marius van Oers notes in McAfee's Labs Blog. "One shouldn't run by default with root access so adding/modifying system binaries should, in theory, not be that easy to achieve. Nevertheless *nix rootkits do also exist, so a perfect guarantee can't be given."

Also, given the size of Apple's installed base, you might expect to see more malware for OS X, van Oers notes. Not least because malware writers no longer look to make massive attacks instead focussing on targeted objectives.

"Nevertheless it is clear that OS X malware is not taking off yet," he says. "With an estimated OS X market share of about five per cent on the desktop systems [and arguably a larger share of the total number of computer users] one would expect to see more malware for OS X."

One conclusion that could be drawn is simply that Apple has successfully endeavoured to make OS X the most secure operating system available, but that is not a conclusion that van Oers is prepared to make.

"It's hard to predict if the number of malware for OS X will remain very low or if it will increase significantly - so stay tuned!!," he said.

All the evidence would seem to suggest that it is quite easy to predict. The recent Month of Apple Bugs project may have found 31 potential flaws in OS X. Of those, the five that did pose a slight risk were quickly patched by Apple. None resulted in a successful malware exploit.

Nonetheless, Apple, while extolling its operating system's security, guards against complacency.

"A Mac running with factory settings will protect you from viruses much better than a PC, but it's never a bad idea to run extra virus and security software," it advised.