17 - LONDON, ENGLAND - NOVEMBER 20: (UK TABLOID NEWSPAPERS OUT) Emma Watson attends the UK premiere of My Week with Marilyn at The Cineworld Haymarket on November 20, 2011 in London, United Kingdom. (Photo by Dave Hogan/Getty Images)
Rupert Grint, Emma Watson and Daniel Radcliffe attend the premiere in Trafalger Square, London, England.
McAfee said Monday that the "Harry Potter" star is the "most dangerous" celebrity to search for online.
That's because many sites use Watson to trick users into downloading malicious software or to steal personal information.
When searching for the 22-year-old Watson, there's a one-in-eight chance of landing on a malicious site.
This is the sixth time the Intel-owned security technology company has conducted the study, which was last year topped by Heidi Klum.
Female celebrities are far more likely to be utilized by cyber criminals: late-night host Jimmy Kimmel was the only male in the top 20.
Others among the riskiest celebrities to search online are Jessica Biel, Eva Mendes, Selena Gomez and Halle Berry.
(Copyright 2012 by The Associated Press. All Rights Reserved.)