One of the traits of the Conficker worm is the blocking of url strings. This includes urls of antivirus companies, Microsoft and support sites that could aid users in removing the Conficker worm from a computer system. Users with the worm cannot open the websites in their web browser anymore and this is the exact concept of the Conficker Eye Chart. It displays six images on the website. Three images from urls that are not blocked by Conficker and three that are blocked.

If the web browser is displaying all six urls it is very likely that Conficker has not infected the computer system. If only the safe three images are displayed an infection with the C variant of Conficker is likely while the display of four images hints at A and B variants of Conficker.

The major benefit of this Conficker detection test is its simplicity. It takes only a web browser and a few seconds to test if the computer system has been infected. It is still a good idea to confirm the findings by using a software detection program which you can find here.