Secret Crush widget spreads adware on Facebook

A "malicious widget" on Facebook is leaving love-hungry social networkers feeling crushed.

The widget - which poses as a "Secret Crush" request inviting prospective marks to find out which of their friends might have the hots for them - acts as a social worm, prompting users to unwittingly download the infamous Zango adware application, security appliance firm Fortinet warns. Users tempted into installing the application are told they need to invite at least five friends before they'll be able to get any further.

Even after that step, no crush of any sort is revealed and the abused user is left facing the frame inviting users to install Crush Calculator. This ap is hosted in the affiliates section of Zango's website and downloads the adware application onto victims who proceed with the download.

Zango was established as a rebranding exercise following the 2006 acquisition of Hotbar by 180solutions. The firm publishes Hotbar, Seekmo Search Assistant, and other adware programs of dubious merit.

The tactics used to seed the application in this case are subtle, and proving effective. Those who have seeded the program within Facebook are cashing in, getting rewarded "per click" as Zango affiliates.

The widget is already being used by three per cent of the Facebook community or around one million users, according to Fortinet which has published an advisory containing screenshots that document the threat.

"Unlike many social worms, the 'Secret Crush' propagation strategy does not rely on phishing or any sort of user-space customisation feature abuse. Rather, it relies on pure social engineering which is based on simple manipulation strategies such as 'escalation of commitment'. Since users have freely chosen to install the widget at the cost of disclosing their personal information, psychologically speaking it is difficult for them to stop the process at that point," Fortinet notes.

Fortinet has warned Facebook of the problem. We're waiting to hear back from Facebook on our requests for comment.

Facebook users can find the offending Secret Crush application at http://www.facebook.com/apps/application.php?api_key=64e35ff1e9860c511f9b79918472fa70 ®