SAN FRANCISCO — A British intelligence agency collected video webcam images — many of them sexually explicit — from millions of Yahoo users worldwide, regardless of whether they were suspected of illegal activity, according to accounts of documents leaked by Edward Snowden.
The surveillance effort operated by Britain’s Government Communications Headquarters, or GCHQ, was code-named OPTIC NERVE. Images from Yahoo Messenger webcam chats were captured in bulk through the agency’s fiber-optic cable taps and saved to a GCHQ database.
It is unclear how much of the data was shared with U.S. officials at the National Security Agency (NSA), although the British ran queries of the data using a NSA search tool called XKeyscore, according to a report Thursday by The Guardian newspaper.
Like the NSA’s collection of millions of people’s phone, email and credit-card data, the webcam surveillance program was carried out in bulk, creating a massive database where the communications of hundreds of thousands of people could later be scanned by analysts for clues or patterns.
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However, unlike the phone database, OPTIC NERVE also automatically downloaded the content of video communications, taking a screenshot from the video feed every five minutes, The Guardian said. One snippet of a leaked document published to The Guardian website appears to show that GCHQ hoped to eventually “collect images at a faster rate,” or perhaps download all the webcam videos in their entirety.
Even at one screenshot every five minutes, material published to The Guardian’s website appeared to show British analysts being deluged with X-rated footage.
“It would appear that a surprising number of people use webcam conversations to show intimate parts of their body to the other person,” another snippet of an intelligence document published said. It went on to say that an informal study had found that between 3 and 11 percent of all the images carried “undesirable nudity.”
It’s not clear how many Yahoo users were spied on in this way. The Guardian said that in one six-month period in 2008, GCHQ intercepted the video communications of 1.8 million users, but it’s possible that the program, which The Guardian says was active in 2012, has either grown or shrunk since then.
If the program expanded, millions more could have had their video communications intercepted. Yahoo Messenger had 75 million users worldwide in late 2011, according to an estimate by digital analytics company comScore, although numbers have fallen steadily since then.
The stockpiling of sexually explicit images of ordinary people had uncomfortable echoes of George Orwell’s “Nineteen Eighty-Four,” where the authorities — operating under the aegis of “Big Brother” — fit homes with cameras to monitor the intimate details of people’s personal lives.
“At least Big Brother had the decency to install his own cameras,” British media lawyer David Banksy said in a message posted to Twitter after the revelations broke. “We’ve had to buy them ourselves.”
The collection of nude photographs also raises questions about potential for blackmail. The NSA has acknowledged that some analysts have been caught trawling databases for inappropriate material on partners or love interests. Other leaked documents have revealed how U.S. and British intelligence discussed leaking embarrassing material online to blacken the reputations of their targets.
The Guardian said the webcam-related documents were provided by Snowden, who remains in Russia after having sought temporary asylum there.
The report did not indicate whether the agency also collected webcam images from similar services, such as Google Hangouts or Microsoft’s Skype. The Guardian did say the British intelligence agency was studying the possibility of using the cameras in Microsoft’s Kinect devices, which are used with its Xbox game consoles, to spy on users.
Because the British agency lacked the technical means to filter out the content of British or U.S. citizens and because it faces fewer legal restrictions than the NSA in the United States, documents show that the GCHQ was collecting vast numbers of webcam images.
The British agency
also apparently experimented with facial-recognition technology, which searched webcam images for faces resembling those of GCHQ targets. One undated document shows that the agency shuttered this capability. It was unclear if or when it was resurrected. It is also unclear if the NSA also had access to the metadata and images.
Yahoo said Thursday that it was not aware of the program and expressed outrage at published reports. “This report, if true, represents a whole new level of violation of our users’ privacy that is completely unacceptable, and we strongly call on the world’s governments to reform surveillance law consistent with the principles we outlined in December,” the company said.
Microsoft also said it had never heard of the surveillance program or the British government’s interest in using the Kinect camera for spying.
Previous disclosures from documents released by Snowden show that the NSA was exploring the video capabilities of game consoles for surveillance and that NSA analysts infiltrated virtual games such as “World of Warcraft” and “Second Life” to snoop on targets.
Internet services send vast amounts of data — including video and webcam chats — through the fiber-optic lines between their data centers around the world. After recent disclosures about government tapping of some such lines, all three companies have said they are working to encrypt those links between their data centers to thwart spying.
Yahoo has said encryption will be in place for all of its services by March 31. Google has encrypted its video chat services, including Hangouts, since at least 2010.
In response to earlier concerns about potential government surveillance of the Kinect camera, Microsoft said last year that it would allow users to turn it off. It also said it did not give any government broad access to Skype data or security technologies.
GCHQ refused to answer questions about OTPIC NERVE, instead returning the same boilerplate answer it has given for months. “It is a longstanding policy that we do not comment on intelligence matters,” the agency said, insisting all its work was legal, necessary, proportionate, and subject to rigorous oversight.
Vaneé Vines, an NSA spokeswoman, said in a statement: “The National Security Agency does not ask its foreign partners to undertake any intelligence activity that the U.S. government would be legally prohibited from undertaking itself.”