Just like the old Amiga game of the same name, the Flashback trojan isn't much fun
OpenDNS, the DNS provider of choice to the discerning and paranoid, is blocking the Flashback Trojan. Once it has infected your Mac, Flashback attempts to “call home” to a server to receive further instructions.
Business Macs that don't include centrally managed antivirus protection may be ticking time bombs
The after effects of the Flashback Trojan are going to be felt for a long time to come. Although there’s been the occasional Mac malware announcement over the past few years, none was ever found to be rampant in the wilds of the Internet. Most were easily avoided by Apple’s basic security elements or by simple user actions like telling Safari not to immediately open so-called “safe” files after downloading them.
As a result, the Flashback Trojan caught a lot of people off guard – including individual Mac owners and some IT professionals who ought to have known better. It also highlighted deficiencies on the part of Apple when it comes to security.