Is Facebook Fan Check a virus? Careful whom you ask

A Facebook application, titled "Facebook Fan Check," has generated quite a frenzy on the website, prompting users to ask "Is it a virus?"

The application, which recently appeared on the social networking site, generates a list of top Facebook friends depending on how much they post on a person's wall or comment on photos.

Already, anti-Facebook Fan Check groups such as "GET FACEBOOK TO BAN FACEBOOK FAN CHECK" and "Let's get Facebook to remove fancheck!" have formed, drawing between 100 to over 1,000 members.

But are the rumors true? What is "Facebook Fan Check" exactly? And is it harmful?

Currently, Facebook users have posted status messages claiming "...that The FAN CHECK application is a VIRUS that takes 48 hours to kick in. Even if you are tagged in a photo the virus still attacks you. Please inform all your friends and remove/delete this application ASAP."

The application has grown in popularity since its launch. Last Tuesday, the Facebook Fan Check page listed 12.5 million monthly active users, NetworkWorld reported. Later that afternoon, after a withdrawal of concerned Facebook users, only 6.4 million remained.

PC World reports that the real danger may be searching for a website that will remove this rumored virus:

"Malicious hackers are setting up malware-infested Web sites that falsely claim to remove a virus from a new Facebook application called Fan Check, security vendor Sophos is warning.... [A]s Facebook members use popular search engines to find antivirus information about Fan Check, they are getting results that point to sites that can infect their computers with malwar," Mr. Carlos writes.

The Internet security company, Sophos, has posted a YouTube video (posted below), demonstrating what happens when you search for anti-virus software to remove Facebook Fan Check. The short video shows that clicking on a link in hopes of removing the application leads to a "bogus" anti-virus software that can take control of one's computer.

Though Sophos hasn't yet confirmed if the Fan Check application is harmful by itself, company blogger Greg Cluley writes that "the fear about the application is leading Internet users into danger."

[H]ackers have set up websites pretending to be about the "Facebook Fan Check Virus", but which really host fake anti-virus software which display bogus warnings about the security of your computer in an attempt to get you to install fraudulent software and cough-up your credit card details.

In a Softpedia article, the creator of Facebook Fan Check, Janakan Arulkumarasa, a developer based in Hong Kong, defends his application from virus rumors, saying it "is NOT a malicious app. Unfortunately, some malicious developers have been spreading a lie that is – and encouraging people to download fake virus scanning software, which damages their computer. This is very unfortunate, but has nothing to do with us."

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