An alleged hack of Apple’s iCloud accounts of many celebrities seems to be the cause of the leakage online hundreds of naked photos purportedly belonging to more than 100 actors and singers. On Sunday, the pictures of 101 celebrities, including Ariana Grande, Jennifer Lawrence, Victoria Justice, Kate Upton, Kim Kardashian, Rihanna, Kirsten Dunst and Selena Gomez. The images were posted on the online image sharing forum 4chan, and rumors report that the pictures were obtained from the celebrities’ accounts on the Apple iCloud service.
Anonymous users on 4chan claimed to have taken them from the service, despite Apple doesn’t commented the event, the analysis of the image metadata confirms that the majority was taken using an Apple device. A detailed analysis of the metadata related to the image leaked online was published on Pastebin, the photos found in a first lot released online are related to a period from December 2011 to 14 August 2014.
The anonymous user who first posted the celebrities’ photos claimed to have other pictures and explicit videos of Lawrence and requested donations via PayPal and Bitcoin for posting them.
The iCloud service allows Apple users to automatically store their data online, including photos, documents and emails. Users can access to their documents from anywhere once authenticated to the service.
It’s unlikely that hackers have compromised the Apple iCloud service, alleged attackers most likely used some hack to target specific accounts. It’s likely that the threat actor initially have compromised the iCloud account belonging to one or more celebrities, then “chaining” between accounts have obtained the access to the victim’s address book to gather data for further attacks.
There are many ways to violate the users’ account, an attacker could guess the users’ credentials (this is usually possible when the attackers have deep knowledge of their victims), conduct a social engineering attack, steal the sensitive data with a malware, or simply resetting victim’ accounts by finding the associated email address and then answering to ‘security questions’.
The website The Next Web, after the publication of the photos, has revealed the existence of a code for the hacking of iCloud service that was posted to the open-source website GitHub.
The application exploits a vulnerability, already fixed by Apple, in the Apple’s ‘Find my iPhone‘ service to guess passwords with unlimited attempts without being locked out.
Practically the attacker can brute force the victim’s account, an operation that could be improved by choosing the passwords from a dictionary of words and phrases, the choice of these databases could be supported by the knowledge of the victims, of their habits and their preferences.
One of the victims, Jennifer Lawrence, has confirmed the authenticity of her pictures, security experts are speculating that photos may have been stolen from victims’ Dropbox accounts, someone else has hypothesized that insiders “with access to data somewhere made a private stash” and was subsequently hacked by the individual who leaked the pictures online.
However Apple has always declared that iCloud backups are encrypted:
“This means that your data is protected from unauthorized access both while it is being transmitted to your devices and when it is stored in the cloud.” states the company in official documentation.
The incident has raised the questions about the level of security offered by online services like the cloud storage, in May, another another incident caused serious problems for Apple users in Australia. Cybercriminals have targeted a large number of Apple’s iCloud users with a sophisticated extortion scheme based on ransom request, the attackers allegedly hijacked Apple’s Find My iPhone feature, in this way criminals remotely lock iOS and Mac devices and send messages demanding ransom money.
At the time I‘m writing Apple has still issued no official statement on the incident, but InfoSec Taylor Swift warned that other celebrities may have been impacted:
“_This is just the beginning._ Folders of images with thumbnails visible have been shown, many celebs yet to be impacted who will.”
(Security Affairs – Data leakage,Apple iCloud)
Apple has released an update to Celebrity photo investigation, the company confirmed that the picture were stolen from celebrities’ accounts which suffered a “very targeted attack”, but its engineers exclude that the breach was caused by the exploitation of any flaws in the iCloud architecture neither the Find my iPhone feature.
“After more than 40 hours of investigation, we have discovered that certain celebrity accounts were compromised by a very targeted attack on user names, passwords and security questions, a practice that has become all too common on the Internet. None of the cases we have investigated has resulted from any breach in any of Apple’s systems including iCloud® or Find my iPhone. We are continuing to work with law enforcement to help identify the criminals involved. “ states the Apple advisory.