For the past six years, Security firm McAfee has compiled an annual list of the riskiest Hollywood actors, athletes, musicians, politicians, designers and comedians on the web.
The 2012 list has once more revealed that women are far more dangerous than men online. In the firm's top 20 most 'risky' celebrities, Jimmy Kimmel was the only male.
Funnyman Kimmel came in at number 13, while Piers Morgan and Brad Pitt dropped off of the top 20 entirely from number three and number 10 respectively last year. Supermodel Klum also slipped out of the top ten.
British actress Watson topped the chart, ahead of Jessica Biel in second and Eva Mendes in third. Latina women made up five of the top ten spots, including Mendes, Selena Gomez, Shakira, Salma Hayek and Sofia Vergera.
Cyber-criminals often use the names of popular celebrities to lure people towards sites that contain malicious software that is designed to steal passwords and personal information.
This year, searching for a celebrity name with "free downloads" and "nude pictures" as part of the search term resulted in the highest result of risky sites, said McAfee.
"In today's celebrity culture, consumers expect to be able to go online to catch up with the latest photos, videos, tweets, and stories about their favourite celebrities," said Paula Greve, director of web security research at McAfee.
"Due to the richness of the data and the high interaction, often times consumers forget the risks that they are taking by clicking on the links.
"As the sophistication and expectations of consumers with respect to their online experience has increased, so has the level and ability to deliver malware either by malvertising, exploiting the user's browser without their awareness, or masking malicious URLs behind shortened URLs."
Watson led the list as there was nearly a one-in-eight chance of landing on a malicious site by searching for her name.
Fans who searched "Emma Watson and free downloads," "Emma Watson and nude pictures," "Emma Watson and fakes," and "Emma Watson and busted" were particularly at risk of being exposed to malware and viruses.
McAfee found that searching for the latest Emma Watson pictures and downloads yielded a 12.6% chance of landing on a website that had tested positive for online threats such as spyware, adware, spam, phishing, viruses and other malware.
The top 10 list in full runs as follows:
1. Emma Watson.
2. Jessica Biel (2009's most risky online celebrity)
3. Eva Mendes (new entry)
4. Selena Gomez.
5. Halle Berry.
6. Megan Fox (up from 15 last year).
8. Cameron Diaz (2010's most dangerous cyber celebrity).
9. Salma Hayek.
10. Sofia Vergara.
McAfee found that bad publicity was not necessarily key for celebrities to increase their 'risk', as Tom Cruise, Katie Holmes, Kristen Stewart and Robert Pattinson did not feature in the top 50, despite all hitting the headlines.
"Hot movies and TV shows, awards and industry accolades seem to be more of a factor than headline-grabbing activity," said Greve.
"Still, searching for any celebrity can bring up risky sites and the public should use caution by not clicking on any page that looks suspicious."