Conficker worm

Conficker worm , also known as Downup, Downadup and Kido, is a computer worm targeting the Microsoft Windows operating system that was first detected in November 2008. The worm uses a combination of advanced malware techniques which has made it difficult to counter, and has since spread rapidly into what is now believed to be the largest computer worm infection since the 2003 SQL Slammer.

At first, Conficker spread through  the Microsoft operating system vulnerability MS08-067 which allows a remote attacker to execute a script on any Windows 2000, Windows XP, Windows Vista, Windows Server 2003, Windows Server 2008, and Windows Server 2008 R2 Beta machine.

The Conficker worm brought chaos upon the world, in got the French Navy, United Kingdom Ministry of Defence, unified armed forces of the Federal Republic of Germany and the the British  House of Commons.

Later on, the Conficker worm updated it self from Conficker A to B, C, D, and E. enabling it to propagate by flash disks and MP3 players and through unsecured network shares.  And with that, the worm developers started to make money out of it by installing some scareware that shows some fake alerts about being infected by some malware and force the victim towards buying a fake security software to fix the infection.
Being unable to keep up with the  Conficker worm Microsoft has offered  $250,000 bounty for Conficker creators.

There is a very funny method to check ifyou are  infected or not by going here. you will see a table with a picture in each cell. if for some reasons some pictures won’t load in your browser, then congratulations you ARE infected. This method exploits the fact that the Conficker worm prevents the infected computer from accessing security websites. The page tries to load some security websites logos from thier original servers, if you are infected the worm will prevent loading the pictures from these sites leaving you with only the open source OS logos (see the page for more details)

You can prevent getting infected by keeping your OS up to date to block all vulnerabilities also update your antivirus daily and hope for the best.

If you are already infected you can check out the following pages for some good fixes