The vast amount of personal data for sale online is an "increasingly powerful" tool for intelligence gathering by US and foreign spying agencies but also represents a privacy risk to ordinary people, according to a newly declassified US intelligence report.

To protect civil liberties, US spy agencies need to catalog what data they buy and develop guidance for protecting that data, according to the report released by the Office of the Director of National Intelligence on Friday.

The report is one of the more detailed public records of how the US intelligence community approaches "commercially available information" -- things such as geolocation data and phone records, which can be bought from third parties. The amount of such data available to anyone with a credit card has exploded in the past decade as smartwatches and wireless earpieces have become a staple of life.

The ubiquity of such data on large groups of people is an "increasingly significant part of the information environment" in which US spy agencies must function, the ODNI report says.

The report was completed in January 2022 but only recently declassified. Democratic Sen. Ron Wyden of Oregon asked the ODNI for the report.

"Congress needs to pass legislation to put guardrails around government purchases, to rein in private companies that collect and sell this data, and keep Americans' personal information out of the hands of our adversaries," Wyden said in a statement Monday in response to the report.

Commercially available data is a dual-edged sword for US government agencies: It opens up new avenues for spying on foreign adversaries while also exposing vulnerabilities to US personnel.

The Pentagon in 2018 announced a ban on deployed personnel using fitness trackers, smartphones and potentially even dating apps that use geolocating features. That followed a review of such practices after Strava, a fitness tracking app, may have inadvertently revealed the locations of security forces around the world.