By Ashkan Soltani, Andrea Peterson, and Barton Gellman

(Photo credit: Key Foster)

The National Security Agency is secretly piggybacking on the tools that enable Internet advertisers to track consumers, using “cookies” and location data to pinpoint targets for government hacking and to bolster surveillance.

The agency’s internal presentation slides, provided by former NSA contractor Edward Snowden, show that when companies follow consumers on the Internet to better serve them advertising, the technique opens the door for similar tracking by the government. The slides also suggest that the agency is using these tracking techniques to help identify targets for offensive hacking operations.

For years, privacy advocates have raised concerns about the use of commercial tracking tools to identify and target consumers with advertisements. The online ad industry has said its practices are innocuous and benefit consumers by serving them ads that are more likely to be of interest to them.

The revelation that the NSA is piggybacking on these commercial technologies could shift that debate, handing privacy advocates a new argument for reining in commercial surveillance.

Read More NSA uses Google cookies to pinpoint targets for hacking.