Does affect Macs
The example that is linked to shows the alert message a person will get if they surf to the fake porn page using Windows and Internet Explorer, but this malware also has a Mac flavor and will attempt to infect people using Mac browsers (including Safari and Firefox).
Anyone on any platform using any Web browser who attempts to "play" one of the promised "movies" will see what looks like a Windows XP Internet Explorer popup window complaining that a new ActiveX control must be installed. The fact that the phony popup looks like an XP dialog window should be a tipoff to Linux, Mac, and Vista users.
In fact, the phony popup "window" is just a graphic, and clicking on it will try to download the malware.
When a user clicks on the phony "dialog" the software on the back end looks at the browser's user-agent strings. If the user-agent string is a Windows browser, it attempts download of a Windows .exe file. If the user-agent string shows a Mac browser, it downloads a file called "QuickTime.dmg" which contains a Mac installer.
If a Mac user downloads the .dmg, then mounts it, then runs the installer, then enters his administration password, then the Mac user will be infected with malware which silently changes the Mac's DNS settings and installs a cron task which will periodically change them again should the user attempt to reset them.
This is nothing new. The Zlob gang has been doing the same thing for over a year; the Mac version of the Zlob malware is occasionally downloaded from nearly identical sites if the site sees a Mac user-agent string.
When ESThosts went dark a while back, the Mac community caught a break; the Mac malware was served up from IP addresses in ESThost's range, and the people responsible for it soon moved the Windows malware downloaders to new servers but it took them quite a while to restore the Mac download servers.
It's a very crude social engineering trick--the phony popup dialogs are designed to look like Windows dialogs, and they talk about installing an ActiveX control. The Mac malware can not install itself (it requires user action and the entry of an administrator password to be installed). It's also not a new trick; the only novel twist is the particular strain of malware being downloaded.
I talked about this at length quite some time ago: