SMS delivery reports

SMS delivery reports can be used to infer the recipient's location. This is because the timing of the delivery report can be used to determine the distance between the sender and the recipient.

SMS delivery reports, which provide confirmation that a text message has been successfully delivered to the recipient's device, typically do not contain explicit information about the recipient's location. However, they can indirectly reveal some details that could be used to infer the recipient's location in certain scenarios.

A team of university researchers have devised a new side-channel attack named 'Freaky Leaky SMS,' which relies on the timing of SMS delivery reports to deduce a recipient's location.

SMS delivery reports are handled by the SMSC (short message service center) of the mobile network to inform when a message has been delivered, accepted, failed, is undeliverable, has expired, or has been rejected.

Researchers have developed machine learning algorithms that can use the timing of SMS delivery reports to infer the recipient's location with a high degree of accuracy. In one study, researchers were able to infer the recipient's location with an accuracy of up to 96% for locations across different countries and up to 86% for two locations in the same country.

This information can be used by cyber criminals to track the movements of their victims. For example, a cybercriminal could send an SMS to a victim and then use the delivery report to track the victim's location as they move around.

However, the potential privacy implications of SMS delivery reports should be considered, especially in situations where the recipient's location needs to be kept confidential. If location privacy is a concern, individuals should be cautious about using services or applications that rely heavily on SMS delivery reports or consider alternative means of communication that do not expose this information.

If you think that your location has been compromised, you should change your passwords and contact your mobile carrier.

Dr. Deepak Kumar Sahu, President & CEO, VARINDIA