NEW YORK (CNN/Money) - Paris Hilton has a problem keeping her personal life personal.
The slinky socialite's latest saga involves highly sensitive details, including phone numbers and personal notes, posted for all to see on the Internet in what could be a case of mobile device hacking.
A spokesman for T-Mobile confirmed earlier reports that information from Paris Hilton's star-studded address book has been posted online.
"Her information is on the Internet," said Bryan Zidar. "We don't know if it was hacked or if someone got a hold of her password."
According to Zidar, Hilton used the Sidekick II, a multi-purposed personal electronic device that uses an online server to store at least some information, including phone numbers.
While Zidar said it is possible for the information on that device to be hacked from the company's server remotely, the company is still investigating the specifics of Hilton's case.
Zidar said that since Sunday night a number of sites had posted Hilton's personal contacts, but the sites kept changing as the Secret Service, which Zidar said investigates computer crimes, shuts them down.
"As soon as one comes up the secret service is all over it," he said.
Names on Hilton's contact list include Christina Aguilera, Anna Kournikova, Ashlee Simpson, Fred Durst, Eminem, Usher, Avril Lavigne, Lil' John, Ashley Olsen, Vin Diesel and the charity Feed the Children, according to e-mails from people who captured some of the posted listings.
A software security expert said anyone who uses Web-based technology to store personal information is potentially at risk.
"If they were able to target her, it would probably take even fewer steps to get information from random people," said Gregg Mastoras of Sophos, a UK-based software security company.
Mastoras said that while security issues surrounding mobile devices were not one of his top concerns, he said the growing popularity of the devices coupled with wireless technology such as Bluetooth, which allows them to communicate with one another even while they are not in use, is opening the door for greater problems.
He cited one virus known as Cabir, which spreads over smart phones. The virus infects the phone's software and turns all its icons into skulls and crossbones, rendering them useless.
"We expect to see some viruses out there that will do some pretty interesting stuff," he said.
Mastoras said that while the viruses could cause the loss of data on a mobile phone such as contact numbers, the phone itself could most likely be repaired by reinstalling the software.
As far as protection from hackers or thieves, Zidar said users could better guard themselves by choosing a difficult password and not giving it out to anyone, not responding to suspect online solicitations for their password and by contacting their service provider should the device be stolen or lost.