aka FreeVideo Trojan, or OSX.RSPlug.A Trojan Horse, etc.
I've seen just a couple so far but expect that there will be more.
The good news is that there is a tool available to fix the problem...
DNSChanger Removal Tool detects and removes latest spyware targeting Mac OS X. DNSChanger Trojan (also known as OSX.RSPlug.A Trojan Horse) attacks users attempting to play a fake video file.
Upon attempting to play the video, the victim receives the following message:
Quicktime Player is unable to play movie file.
Please click here to download new version of codec.
Upon running the installer, the user’s DNS records are modified, redirecting incoming internet traffic through the attacker’s servers, where it can be hijacked and injected with malicious websites and pornographic advertisements. The trojan also installs a watchdog process that ensures the victim’s DNS records stay modified on a minute-by-minute basis.
SecureMac’s DNSChanger Removal Tool allows users to check to see if the trojan has been installed on their computer; if it has, the software helps to identify and remove the offending file. After a system reboot, the users’ DNS records will be repaired.
This tool is free.
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