The site, Ashtonhacked.com, offers several recorded messages including one from a young lady -- and not his girlfriend Demi Moore -- recounting a sexual encounter with the "Punk'd" star, the New York Daily News said Sunday.
The Boston man who owns the Web site told the Daily News Kutcher was "punk'd" by two high school kids he met while playing Xbox Live.
He said they told him they got Kutcher's cell phone number through "a friend of a friend, somebody who works at MTV." So he registered the Web site and turned it over to the hackers.
He also told the Daily News he is convinced the voice-mails are real.
"I can't imagine these guys would have the ability to fake it," he said. "Much easier for me to believe they stayed up all night hacking his phone."