One of the National Security Agency’s most powerful tools of mass surveillance makes tracking someone’s Internet usage as easy as entering an email address, and provides no built-in technology to prevent abuse. Today, The Intercept is publishing 48 top-secret and other classified documents about XKEYSCORE dated up to 2013, which shed new light on the breadth, depth and functionality of this critical spy system — one of the largest releases yet of documents provided by NSA whistleblower Edward Snowden.
These servers store “full-take data” at the collection sites — meaning that they captured all of the traffic collected — and, as of 2009, stored content for 3 to 5 days and metadata for 30 to 45 days. NSA documents indicate that tens of billions of records are stored in its database. “It is a fully distributed processing and query system that runs on machines around the world,” an NSA briefing on XKEYSCORE says. “At field sites, XKEYSCORE can run on multiple computers that gives it the ability to scale in both processing power and storage.”
Beyond enabling the collection, categorization, and querying of metadata and content, XKEYSCORE has also been used to monitor the surveillance and hacking actions of foreign nation states and to gather the fruits of their hacking. The Intercept previously reported that NSA and its allies spy on hackers in order to collect what they collect.
Once the hacking tools and techniques of a foreign entity (for instance, South Korea) are identified, analysts can then extract the country’s espionage targets from XKEYSCORE, and gather information that the foreign power has managed to steal.
Monitoring of foreign state hackers could allow the NSA to gather techniques and tools used by foreign actors, including knowledge of zero-day exploits—software bugs that allow attackers to hack into systems, and that not even the software vendor knows about—and implants. Additionally, by monitoring vulnerability reports sent to vendors such as Kaspersky, the agency could learn when exploits they were actively using need to be retired because they’ve been discovered by a third party.