Over the weekend, attackers posted explicit pictures of Hollywood celebrities including Oscar winner Jennifer Lawrence, allegedly obtained via a vulnerability in Apple's iCloud service.
The pictures were posted on the 4chan site, where users often share explicit pictures. The original poster claimed to have additional photos for which payment was being sought.
Spammers tend to attempt to get naive users to click on links including explicit pictures, leading some people to initially think that the images were fake. Some of the celebrities confirmed the pictures were real, however, while others said they were fake.
"Knowing those photos were deleted long ago, I can only imagine the creepy effort that went into this," actress Mary Winstread tweeted. "Feeling for everyone who got hacked."
According to multiple reports, a spokesperson for Lawrence also confirmed the authenticity of the pictures and expressed anger at the flagrant violation of privacy. Not all the pictures, however, are authentic.
"These so called nudes of me are FAKE people," actress Victoria Justice tweeted. "Let me nip this in the bud right now. *pun intended*"
While the actual root cause of the picture leak has not authoritatively been confirmed, there is widespread speculation that the pictures were stolen from Apple's iCloud service.
"We take user privacy very seriously and are actively investigating this report," Nat Kerris, an Apple spokeswoman, told NBC News .
Actress Kirsten Dunst, pictures of whom were also released in the attack, took specific aim at iCloud too.
"Thank you iCloud," Dunst tweeted.
The NBC News report noted that the FBI is actively investigating the incident.
The alleged iCloud flaw is linked to a possible brute force vulnerability in the platform. In a brute force attack, the hacker uses an automated tool to guess username and password combinations in an attempt to gain access.
Specifically, an iBrute brute force attack may have been responsible for the celebrity picture leak. A proof of concept outlining the attack was publicly posted on the Github code sharing site.
"It uses Find My Iphone service API, where bruteforce protection was not implemented," the iBrute Github page states.
The Find My iPhone service is Apple's service that is supposed to help users locate a lost or stolen iPhone device. While Apple has not publicly confirmed that there is any issue, the iBrute Github page notes that Apple has now patched the flaw.
This isn't the first time in 2014 that a vulnerability in Apple's Find My iPhone service has been implicated as the root cause of an attack against users. In May, Apple users in Australia had their iOS devices held for ransom by an attacker who allegedly hacked the Find My iPhone service.
Cloud Storage Security
If Apple's iCloud is in fact at the root cause of this latest attack, it raises some serious concerns about the state of cloud storage security. Are files stored in the cloud more or less secure than files stored anywhere else?
In this case, if in fact it was a brute force attack, should the cloud service be blamed for not providing adequate protection?
The simple truth is that cloud storage is only as secure as the access methods that are deployed. That is, even if the cloud service itself is potentially at risk, if the system has multiple layers of authentication, a simple brute force attack, which only yields a username/password combination, will not be successful.
If users employ two-factor authentication—a second password (or factor)—a simple brute force attack will not work. Apple does in fact offer two-factor authentication for its AppleID accounts, which are used to access the iCloud service.
That said, it's important to remember that this incident involved theft of personal information. Even if the users didn't have two-factor authentication, and even if the cloud service didn't have proper brute force protection, a crime did occur. Users and cloud vendors need to do their part to secure users, and in this case, law enforcement now needs to do its part to bring those responsible to justice.
Sean Michael Kerner is a senior editor at eWEEK and InternetNews.com. Follow him on Twitter @TechJournalist.