Transcript for How Did a Massive Celebrity Photo Hack Happen?
And tonight, a new break in a case involving a massive invasion of privacy for some big stars, Ip colluding Jennifer Lawrence and Kate Upton. Hackers broke into their account, stole nude pictureses and leaked them on to the internet. Now, the FBI is son the job. Whether they catch the bad guys or not, this whole thing exposes how vulnerable or most private information can be. And tonight, ABC's Rebecca Jarvis with the investigation and the simple things you can do to protect yourself. Reporter: From Jennifer Lawrence to Kate Upton, it is what could be the largest breach of privacy, racy celebrity photos in history. The FBI telling ABC news, it is investigating exactly how it happened and who is behind it. More than 100 of Hollywood's leading ladies accounts' allegedly accessed, photos stolen and leaked on to underground message boards Sunday night. Now, the pictures and the response from Hollywood going viral. Let's have a big hand for our very first volunteer, katniss everdeen. Reporter: A spokesperson for "Hunger games" star, Jennifer Lawrence, calling it a violation of privacy. Telling ABC news, the authorities have been contacted and will prosecute anyone who posts the stolen photos of Jennifer Lawrence. Model Kate Upton's attorney also confirming the authenticity of the pictures and promising legal action. While some have denied the pictures are real, like "Problems" singer, Ariana grande, legal experts say to expect bigger battles ahead. This could be an uphill battle for the celebrities. First, you have to find the person. That's the toughest battle. Secondly, where did the photos originate? Who took the photos? Who uploaded the photos? That's a big part of where this case actually happens. And if this person is out of this country, you have direction over that person? Reporter: How does something like this happen? Tonight, apple revealing it was not a breach in any of their systems. Including cloud. But instead, a very targeted attack on certain celebrity accounts, including their user names, passwords and security questions. What's your mother's maiden name? The name of your first pet. When you talk about a celebrity, you can probably get this information from their wikipedia wage. Reporter: Deep, underground network of hackers are all over the internet. Searching for this type of material around the clock. And profiting from the brazen sale of celebrity photos like the ones involved in this breach. These underground contests that are going on, you know, in places like message boards, they almost use it as a mark of honor to find this material. It's a race to the bottom. Reporter: Chris is the CEO of insight security. His firm is hired to protect V.I.P.S. And says it's the kind of thing he deals with regularly. One of his major concerns is that these pictures could be used to blackmail or extort the celebrities. Tell me about some of the situations you have found yourself and your clients in. So, the high-profile people who we help with their security have a lot of concerns over privacy. We'll try to feed information to the internet which is neither innocuous or misleading to help people maintain their privacy by making it more difficult to find personal information to them. Once something is on the internet, it's very hard, if not impossible, to take it off. But one successful strategy to try to push it down to make it harder to find. Reporter: But it's not just the rich and powerful. The breach of privacy is also raising major security concerns for the rest of us. Is anybody really safe? The quick answer is no. If there was one piece of data, which is available digitally, which a large number of very competent and motivated hackers want to get to, eventually they will probably get to it. Reporter: That's because it appears that some of the stolen material came from cloud storage accounts. Servers that store all of our data, from our e-mails to our pictures. Even if they're deleted from our phones. Often times, they've already been uploaded to the cloud and continue to exist. Hello. And welcome to joy of sex. Reporter: A consequence played out in the recent movie "Sex tape." It went down to the cloud. You can't get it down from the cloud? Nobody understands the cloud. It's a mystery. Reporter: If you use dropbox, Google, apple or Facebook, your data is in the cloud. How can you protect your own photos and information on the internet? Use unique and separate passwords for all your accounts. Enable two-step verification on all of your apps. First, your user name and password, and a randomly generated private code, sent to your phone via text message. And accept those software update notifications. They arm your smartphone with the latest security protection. The report for those in Hollywood not involved in the breach. Are you kidding me? Reporter: "Girls star," Lena Dunham, tweeting the way you share your body must be a choice. Support these women and do not look at these pictures. So, what exactly is next for the celebrities caught up in this computer screen drama? I think particularly Jennifer Lawrence and Kate Upton have done a smart thing. Most of the time, when something that is completely unexpected happens to you. And a pretty jarring and awkward thing, the first thing you want to do is not tell the truth and say, it wasn't me. They did a smart thing by saying, this was me. And I'm going to sue whoever I can sue. They should sort of keep their heads down and keep working. But they're doing a good job. Reporter: I'm Rebecca Jarvis, for "Nightline" in New York. Our thanks to Rebecca Jarvis. For more tips how to protect yourself online, check out abcnews.com/"nightline." Coming up next on the show,
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