The use of AirTags has raised various issues relating to privacy. At the end of 2022, we learned that two women had filed a complaint against Apple after their ex-partner had spied on them using this accessory. While several methods exist to detect stalking, researchers from Johns Hopkins and California universities have developed a solution intended to strengthen the security of these tracking devices. made in Cupertino.
As a reminder, AirTags rely on the encrypted and anonymous Locate network, made up of hundreds of millions of Apple devices around the world, with which they interact via Bluetooth to indicate their position to iCloud. The data only belongs to the user, their private life as well. That said, the system imagined by Apple has been hijacked several times by malicious people (thieves, jealous spouses, etc.).
Several researchers have therefore designed a cryptographic solution which, according to them, would prevent the tracking of a person by an unscrupulous person using an AirTag. Currently, the accessory rings after a certain period away from its owner, the latter even being alerted of the situation on his iPhone, but this does not slow down the stalkers who take advantage of this period of time to act.
Secret sharing favored by researchers
The researchers’ cryptographic solution is called “secret sharing,” a method that protects confidential information by making it accessible only when specific conditions are met. For AirTags, this would be the true static identity of the accessory, hidden under the public identifier which would change frequently for privacy reasons.
To put it simply, it’s as if the accessory had a mask that it constantly changes so as not to be recognized. This mask is the public identifier. The true static identity is only revealed when certain conditions are met to ensure the confidentiality and security of the user. This solution would therefore make it very difficult for a malicious person to track an AirTag over a certain period, since they would lose track of it due to the constantly changing public identifier.
Not content with suggesting the sharing of secrets, experts also advocate “error correcting code”a coding technique dedicated to separating useful data from noise to maintain signal quality, even in the event of error or interference.