I must admit to being in the camp that says "yes, it could happen one day," and that's why I've been running antivirus software on my Macs for at least a decade. (Let's not get bogged down in semantic arguments about viruses vs Trojans vs whatever - we all know what we're talking about, and the Mac AV products I've looked at do detect Trojans.)
It seems to me that if there is a significant outbreak of Mac malware, I have more chance of avoiding it if I already have AV software running with frequent checks for updates than I would if I waited for news of an outbreak and then took action. Cost doesn't come into the argument, as there is a choice of free AV programs from major vendors.
But here's what McAfee officials said today:
"Apple: No longer flying under the radar
"Historically, the Mac OS platform has remained relatively unscathed by malicious attackers, but McAfee Labs warns that Mac-targeted malware will continue to increase in sophistication in 2011. The popularity of iPads and iPhones in business environments, combined with the lack of user understanding of proper security for these devices, will increase the risk for data and identity exposure, and will make Apple botnets and Trojans a common occurrence."
So what's changed in the last year or so? Please read on.
And given the general shift from old-school viruses that spread via infected files or removable media, the idea that the Mac population isn't sufficiently dense for malware to spread is no longer relevant.
So I talked to Michael Sentonas, McAfee's Chief Technology Officer for the Asia-Pacific region. "We are seeing more Mac OS X malware coming through [McAfee Labs]," he said., specifically code that co-opts systems into botnets, fake antivirus software, and banking Trojans (as well as more general password-stealing Trojans).
"Slowly we're seeing ports of the common malware" to Mac OS X and mobile platforms, he explained.
"It's so easy to port any code across to [iOS devices] so the risk exposure will become a lot greater over the next 18 months," added Sentonas. Jailbroken iOS devices present more fertile ground for attackers, but if there weren't any vulnerabilities in the platform jailbreaking wouldn't be possible.
He also suggested that the growing number of application stores for various platforms will have an effect. "We will start to see more malware that will target [specific] apps," he said, suggesting that users need to be less trusting.
Sentonas also suggested that people should show more concern for the privacy of their personal information. While it isn't usually too difficult to clean up an infected computer or other device (as long as an adequate backup regime is in place), recovering from a case of identity theft or fraud is more of a problem.