It's unclear how the images were obtained, but anonymous 4chan users said that they were taken from celebrities' iCloud accounts. The accounts are designed to allow iPhone, iPad, and Mac users to synchronize images, settings, calendar information, and other data between devices, but the service has been criticized for being unreliable and confusing. Earlier this year, Jennifer Lawrence herself complained about the service in an interview with MTV.
Several media contacted Apple for more information but they have not commented on this yet.
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