A recently disclosed NSA document from Edward Snowden revealed that the agency has had an inside view of North Korea’s hacking capabilities since 2010, reports The New York Times.

By tunneling into Chinese networks used for wider connectivity by North Korea more than four years ago, the NSA was able to use malware to track the workings of North Korean hackers, who are said to number about 6,000 people in total.

NSA investigators recently determined that the North Korean force had gained access to a Sony systems administrator’s credentials, to explore the company’s network over two months before leaking confidential files and emails, and taking its servers down last year.

Security experts have been skeptical about the minimal evidence released by the FBI, which, according to the bureau, showed that North Korea was responsible for the Sony attack.

These findings about NSA operations to spy on North Korea seem to corroborate the FBI’s claim — but if the agency has been keeping an eye on the North for over four years, it surely must have seen the Sony attack coming and could have warned the company about the imminent attack.

Sony Pictures Entertainment was the victim of a cyber-attack last November, when a hacker group took control of the company’s computer systems, released internal documents and correspondence, and demanded the cancellation of its film The Interview.

We’ve contacted Sony for comment, and will update this post when we hear back.

➤ N.S.A. Tapped Into North Korean Networks Before Sony Attack, Officials Say [The New York Times]

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