The National Security Agency whistleblower Edward Snowden used inexpensive and widely available software to plunder the agency’s networks, it has been reported, raising further questions about why he was not detected.
Intelligence officials investigating the former contractor, who leaked thousands of documents to media outlets including the Guardian last year, determined that he used web crawler software designed to search, index and back up websites to “scrape” highly classified files, the New York Times reported on Sunday.
The unusual activity triggered a brief challenge from agency officials but Snowden persuaded them it was legitimate and continued mining data.
“We do not believe this was an individual sitting at a machine and downloading this much material in sequence,” an unnamed official told the Times. The process, the official said, was “quite automated”.
Web crawlers, also known as spiders, move from website to website, following links embedded in each document, and can copy everything they encounter. Snowden is believed to have accessed about 1.7 million documents.
The NSA has a mandate to deter and rebuff cyber attacks against US computer systems but Snowden’s “insider attack” was relatively unsophisticated and should have been detected, investigators said, especially since it came three years after Chelsea Manning used a similar technique to access State Department and military data which was then passed to Wikileaks.
Snowden was a technology contractor working at an agency outpost in Hawaii that had yet to be equipped with modern monitors which might have sounded the alarm. The NSA’s headquarters in Ford Meade, Maryland, had such monitors, raising the question whether Snowden was “either very lucky or very strategic”, said one intelligence official.
According to The Snowden Files, a new book by Guardian journalist Luke Harding, Snowden moved to a job in Honolulu with security company Booz Allen Hamilton because it afforded even greater privileges.
Some members of Congress have accused Snowden of being a spy for Russia, where he has been granted asylum. He has denied the allegation.
Michael McFaul, the US ambassador to Moscow, declined to be drawn on the subject in an NBC interview on Sunday.
“What I can say,” he said, “is we want Mr Snowden to just come home, face the charges against him, and have a court of law decide what he has and has not done.”