A threat has been detected on the landing page of a search engine optimization (SEO) website, the ad of which is currently running on Facebook.
Webopedia describes Trojan as:
A destructive program that masquerades as a benign application. Unlike viruses, Trojan horses do not replicate themselves but they can be just as destructive. One of the most insidious types of Trojan horse is a program that claims to rid your computer of viruses but instead introduces viruses onto your computer.
Virus Radar first detected the JS/Kryptik.AMG variant on July 9, 2013.
It is believed that the ad is targeted to marketing professionals, page admins, website administrators/owners, bloggers, and SEO experts so it does not appear to most Facebook users.
However, it is advisable to install an anti-virus software that can effectively detect computer threats to ensure protection.