Antivirus XP 2008
Be careful with what you click! This Trojan makes you believe that there are viruses/worms in your computer, makes you download a file named XPantivirus2008_v880421.exe (v880421 is a variable component in the file) and installs another executable named xpa.exe which is a worm. This will create entries in multiple locations including ProgramFiles, Windows Registry and also adds an entry in the System Startup so that it can reappear after reboot.
This was actually reported to us by an infected user who also reported that many users in Australia are affected. The worm is described in more detail here.
Action:
1. Do not open any link that claims to clean the Virus/Worms existing on your computer
2. If you are already infected, AVG Free has cleanup means and others are adding as well, so run your AV scanner.
3. We have Snort signature written for this.