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"In one man-on-the-side technique, codenamed QUANTUMHAND, the agency disguises itself as a fake Facebook server. When a target attempts to log in to the social media site, the NSA transmits malicious data packets that trick the target’s computer into thinking they are being sent from the real Facebook. By concealing its malware within what looks like an ordinary Facebook page, the NSA is able to hack into the targeted computer and covertly siphon out data from its hard drive. A top-secret animation demonstrates the tactic in action.
"The documents show that QUANTUMHAND became operational in October 2010, after being successfully tested by the NSA against about a dozen targets."