ZDNet has been on the ball with respect to the ongoing back and forth between Mac Defender and Apple’s attempts to thwart the malware. Below is video footage where they show how the malware installs itself and originates from what appears to be an innocuous Google search. If you recall, the malware proliferates via Google search results on account of its use of SEO to appear at the top of Google’s search results. Also note that in the video below no password is no required for the malware to install.
In the wake of Apple’s security date, since updated twice to handle a new variant of Mac Defender, this is what users now encounter when they inadvertently trigger the Mac Defender installation process.