According to Sophos, the security company, the net is rife with a new threat on the block. It approaches the users as a genuine Microsoft update, the main difference is being that it is not. It is actually a fake anti-virus rounding up in the grab of Microsoft update, and successful in luring users into trap. These days the criminals uses to convince users to believe that the fake anti-virus that they are being asked to download indeed a genuine update from Microsoft. The update pops-up only when the users are using Mozilla Firefox on Windows, those familiar with Microsoft updates, the genuine ones know they happen only on Windows Explorer. Sophos also stated that the users should comply with such security updates unless they have duly checked its Adobe, Microsoft, or Sophos themselves.