For a long time Macs were pretty much left alone when it came to viruses and Trojans. Thanks to the booming popularity of Mac computers, that isn't the case anymore with more and more attacks coming that are aimed directly at OS X users. One of the latest bits of nefarious software aimed at Mac users is the Flashback trojan.
According to reports, this particular trojan has control of over half a million Mac computers, and the number keeps increasing. That number comes from a Russian antivirus company called Dr. Web. When the trojan was first reported, the antivirus company claimed it controlled 550,000 Mac computers. Later in the day one malware analyst from the company claimed that the number of infected Macs had increased to 600,000 with 274 checking in from Cupertino.
The latest version of the Flashback trojan has been around since last year, and the latest version targeted an unpatched Java vulnerability within the Mac operating system. However, Apple has now patched that Java vulnerability. The image you see here is the result of code F-Secure offers to test and see if your Mac is compromised. Mac users should check their computers ASAP.