On May 20 of last year, Edward Snowden reportedly arrived in Hong Kong carrying "four laptop computers that [enabled] him to gain access to some of the US government's most highly-classified secrets."
The idea that the rogue NSA contractor was carrying NSA documents on laptops that could potentially be compromised led to speculation that Chinese intelligence services could steal the data.
Then, after the 30-year-old flew to Moscow on July 23, a former CIA officer who visited Snowden told Reuters that the laptops in his possession with were a "diversion" and that the secrets he took from NSA systems were stored on highly-encrypted thumb drives.
Both of these theories — that the laptops held NSA data and that they were all decoys — seem to be over-simplistic at this point.
Glenn Greenwald, who met Snowden in Hong Kong and received a set of documents from him, explains in his new book that the NSA systems administrator had "four empty laptops" in Hong Kong with "each one serving a different security purpose."
So Snowden's computers were more than decoys but were probably not housing classified NSA documents.
"Most people aware of high-security needs employ several laptops for segregating the various persons they talk to, and the classification levels of the information they handle," Dave Aitel, CEO of cyber security consultancy Immunity Inc., told BI. "Snowden was used to this from working at the government, and probably used this technique by only handling the documents on one laptop and communicating with the others. That way at no time would his documents ever be directly reachable by someone who hacked one of his communications laptops."
Cyber expert and CEO of TrustedSec David Kennedy detailed how a security system with four laptops and encrypted thumb drives would work in practice.
"You keep separate laptops in order to compartmentalize the data and ensure that only certain data is only on one system vs. the other in order to keep certain types of data that jointly together could be very damaging of taken," said Kennedy, a white hat hacker who breaks into systems for major companies. "Additionally, it may require a certain sequence of laptops and multiple encryption keys in order to disable them."
Given Snowden's assurances that the data was secure, this kind of system would make a lot of sense.
That being said, a significant mystery remains: Snowden and Greenwald said that the NSA-trained hacker stole more NSA documents than he gave journalists, but Snowden then claimed that he gave up everything to journalists he met in Hong Kong.
So it's unclear when he gave up access to the other documents, which U.S. officials say involve highly sensitive U.S. military intelligence.
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