The misinformation and rhetoric surrounding the recent discovery of the Flashback trojan for Macs is vehement, and says more about the historically stable state of Mac security, and the irrational way many think about it than it reveals about its weaknesses. Even long-time industry observers, who should know better, are jumping into the fray to say: See! I told you so! The Mac is vulnerable! Well…duh…that's not exactly news, folks.
Of course the Mac is vulnerable. EVERY internet connected device is vulnerable. What matters is probability, frequency and potential impact. So the correct question then, is whether or not your prevention, detection and recovery mechanisms are effective. For example, I'm not convinced that traditional anti-virus approaches are right for the Mac. The track record of these tools in the Windows world is abysmal in my view. They're among the most intrusive technologies to the user - hogging system resources and making even basic tasks impossible as they inspect every file, every day, often several times a day. And…they're reactive. Think: death by a thousand papercuts over a period of years, only to be interrupted by a rare strain of encephalitis, followed by a partial lobotomy and organ transplant to get the patient breathing again, and you're in the ballpark. Application whitelisting will hopefully come to be seen as a better approach.