The metadata that is associated with telephone numbers isn’t as anonymous as the government, politicians and law enforcement would have people believe.
A new privacy study shows how a lot of detailed personal information can be easily mined from “anonymous” phone number metadata using common internet searches and online public records. According to the study, “Evaluating the Privacy Properties of Telephone Metadata,” researchers were able to find out all sorts of personal information about people just by using metadata from their phone records along with various online search engines.
The research revealed how law enforcement or anyone else with access to a person’s phone number metadata can find out the identity of the phone number owner as well as where they live, businesses they frequent and names of friends, family and associates.
The study even showed how phone number data can be used to find out revealing personal information about someone such as their hobbies, organization affiliations, services that they use and potential medical issues they have. In fact, the researchers identified one volunteer who had a heart condition, based on that person’s phone data.
The study was conducted by a team of Stanford researchers using phone call metadata from 823 volunteers. The phone metadata was collected from the study’s volunteers using a custom app called MetaPhone that was installed on their smartphones. The MetaPhone app gathered up metadata from the volunteers’ smartphones that included their recent call history.
Using the small set of phone call metadata that they collected from the volunteers, the research team then began their search to find out how much detailed personal information they could find out about each person by using publicly available searches. The research team used people search engines, public record searches, internet search engines and social media sites to find out as much information as they could about each person who volunteered for the study.
Some of the publicly available searches that the researchers used included well-known sites like Facebook, Google and Intelius. The results of their study are a privacy advocate’s worst nightmare.
By using people searches, public record databases, search engines and social media sites, the researchers were able to find the full names for the overwhelming majority of phone number owners, showing that phone number metadata is anything but anonymous.
In addition, the researchers were able to use the phone number and call history data to find out areas where volunteers lived and the businesses that they phoned most frequently. Furthermore, the subject’s phone call histories were used to find out personal information on people like religious affiliation, political affiliation, social causes, health care providers etc.
Prior to November 2015, the National Security Agency gathered massive amounts of phone call metadata from every phone number in the United States. Phone number metadata is currently collected and stored by telephone service providers. The NSA now has to get a FISA order to obtain this phone data.
However, even with recent federal laws that restrict access to telephone metadata, the Stanford study estimates that law enforcement and the NSA are still able to obtain metadata for around 25,000 people from just one target person’s phone records.