Over the years, private data collection services have accumulated commercially available information (CAI), which encompasses highly-revealing data on millions of American citizens, including location, smartphone, and web browsing data.

While much of this commercially available data is anonymous, it can be "deanonymized" and used to identify people, according to a recent report from the Office of the Director of National Intelligence (ODNI), released on June 9.

U.S. intelligence agencies have admitted to buying large quantities of this information and are able to tap it for valuable intelligence on unsuspecting Americans, per the report.

The report warned that a lack of standards and procedures around obtaining and handling this data by spy agencies poses risks to people's privacy and even safety.