(New York) Modern cars are a “nightmare” for personal data protection, according to a study published Wednesday by the Mozilla Foundation, according to which they are a wealth of information for manufacturers, who use and resell them at will .

The foundation, based in San Francisco, California, reviewed the models of the 25 most popular brands on the market, and concluded that all, without exception, “collect more personal data than necessary”.

“Cars are the worst product we’ve ever tested for the protection of personal data,” says the Mozilla Foundation, which has already studied connected watches, connected speakers or meditation applications.

In concrete terms, manufacturers are able to enter information related to the use of the vehicle (driving), but also relating to the car’s connected services, as well as third-party applications, such as navigation software or streaming radio.

The on-board software also makes it possible to capture data from a smartphone if it is connected or if its user has downloaded the manufacturer’s application.

Of all the brands, only Renault and Dacia, which are part of the same group, indicate that motorists have the right to request the deletion of personal data collected during the use of their vehicle.

Some 84% of manufacturers mention the possibility of sharing the information collected, and 76% (19) of selling it.

In the ranking of brands according to several criteria relating to the protection of personal data, Tesla comes last.

It owes this place in particular to its “unreliable” artificial intelligence software, according to the Mozilla Foundation, known for its Firefox browser, which claims to be more protective of personal data than its major competitors.

Tesla has been implicated several times for malfunctions in its driver assistance software.

In June 2022, a report by the United States Highway Traffic Safety Agency (NHTSA) listed 273 accidents involving Teslas in which the program was active during the 30 seconds before the event.

The US Department of Justice has opened an investigation into the matter, according to a stock market filing released in late January.

Behind Tesla comes Nissan, which Mozilla has highlighted as potentially extracting data relating to “sexual activity”.

As for the security of this data, 17 of the 25 brands have been the subject of leaks and hacks in the past three years, according to the study.