Los Angeles  - Actress Jessica Biel is the most dangerous celebrity in cyberspace, according to a study released Tuesday by internet security firm McAfee.

The study found the fans hoping to track the exploits of the Hollywood beauty had a one-in-five chance of landing on a website that tested positive for online threats such as spyware, adware, spam, phishing and viruses.

Last year's riskiest celebrity was Brad Pitt, while in 2007 the dubious honour went to Paris Hilton.

Beyonce came second in this year's list, followed by Jennifer Aniston, Miley Cyrus, Ashley Tisdale and Lindsay Lohan. Angelina Jolie, Megan Fox and Brad Pitt also made the top 10.

Celebrity first couple, US President Barack Obama and First Lady Michelle Obama came near the bottom of the list at 34 and 39 respectively.

"Every day, cyber criminals use celebrities' names and images to lure surfers searching for the latest stories, screen savers and ringtones to sites offering free downloads laden with malware," said McAfee in a statement.

"Consumers' obsession with celebrity news and culture is harmless in theory, but one bad download can cause a lot of damage to a computer."  (dpa)