Tests conducted by our threat research team on several computer testbeds have revealed that during the installation process of SystemDefender a Trojan infection starts to perform malicious activities that include the execution of hidden files. SystemDefender is known as a rogue anti-spyware program that when installed it displays popups or messages stating that you have an infection.

Upon further investigation, we’ve detected that it wasn’t just one Trojan but many trojans that are known to be variations of Trojan.Downloader and Trojan Vundo. The Trojans perform several bad actions such as displaying a “Warning” message on your desktop background and not allowing you to open certain programs. These types of Trojan infections can be very detrimental to the operation of your computer.

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