Getting a stranger’s phone kicked off the cellular network costs a few dollars
Researchers show attackers can remotely block strangers' phones and alarm gateways on US cellular networks by abusing lost/stolen IMEI reporting for $2.50-$4 per device.
Researchers from Michigan State University and three partner schools found six weaknesses in the lost/stolen device reporting ecosystem spanning devices, carrier systems, and cross-carrier block-list sharing. They demonstrated blocking unopened Samsung Galaxy Z Fold 7 phones and home alarm gateways on three major US carriers, with each block costing $2.50-$4 and taking roughly 20-80 seconds. The attacks exploit thin identity and ownership checks in prepaid accounts, IMEI leakage from vulnerable cellular chipsets used by two vendors with over 40% global market share, and pre-release IMEI databases purchasable for $600. Victims receive no notification, and restoring service requires proving device ownership to the carrier.