From actress Jennifer Lawrence to model Kate Upton to actress Mary Elizabeth Winstead, these are just some of the names of celebrities victimized by one of the largest hacks of racy celebrity photos in history.

Someone posted nude photos of them and several others, claiming to have exploited a vulnerability in Apple's iCloud service.

Michael Legary, an information security expert, said the hacker exploited a flaw, allowing them to try an infinite number of passwords on the celebrities’ iCloud accounts.

"The tools are cheap and easy to use on the Internet, so it doesn't take much to guess and break into someone's account,” said Legary from Seccuris Inc.

While celebrities were exposed this time, they're not the only ones who may have risqué photos they'd rather keep under wraps.

"Sometimes that happens. You're in a relationship and you send photos to one another and the fact that you can't do that anymore, it's scary. It makes you feel like you can't do anything like that,” said Nicole Thiessen.

To better protect your photos and information online, experts suggest picking unique and separate passwords for your accounts. Enable two-step-verification - both a username and password.

Then, have a separate private code and, finally, keep your security software up to date.

"If you're taking a photo on any digital device, expect for it to be exposed or leaked in the future," he said.

Apple issued a statement Tuesday.

“Celebrity accounts were compromised by a very targeted attack on user names, passwords and security questions. None of the cases we have investigated has resulted from any breach in any of Apple's systems including iCloud or Find My iPhone,” it said it its statement.