Scarlett Johansson's nude photos, leaked onto the Internet last week, were reportedly stolen from her cellular phone.

The actress has sought the help of the FBI, which is investigating a wave of celebrity phone hacking.

Other actresses like Jessica Alba and Vanessa Hudgens have also reportedly had their phones hacked, pictures stolen and released online.

But how do hackers get access to someone's private phone?

According to tech site Gizmodo, there are several ways for this to happen.

There's about as many ways to skim a phone as there are to skin a ginger seal, the site states.

A victim may accidentally give hackers access to the photos in her phone by clicking on a malicious link. E-mails appearing to come from people you know may actually be fakes created by a hacker and if you follow the links, your phone can be hacked.

Gabriel Landau, an analyst at Independent Security Evaluators, told Gizmodo that by clicking on such a link the cell phone user could have invited a Trojan horse onto their handheld device. This trojan virus has the ability to commandeer the smartphone.

When there's a malicious file creeping from a site to your phone it could add code to your phone's Web browser and operating system, and make it send private pictures to unintended recipients.

Malicious programs also can lie in wait on a cell phone.

Once they have this malware running, Landau told Gizmodo, they can monitor your location, and even record with your phone's cameras and microphone.

Lansau said this type of attack is less common because it's much tougher than spoofing an e-mail header or guessing an easy  security question.

Experts suspect that someone most likely broke into an online service Johansson was using to store pictures, not her phone itself.

While she was sending someone else the pictures or using a photo syncing service such as a cloud for sharing, a compromised password or security question guess could have granted a hacker access to her files.

File-syncing services are making it easier for hackers to gain access to other people's property, according to Landau.