SIM Swap Attack

A SIM swap attack, also called SIM splitting or simjacking, is a form of account takeover fraud that exploits a mobile carrier's ability to port a phone number onto a new SIM card, defeating two factor authentication that relies on a text message or phone call. The attacker first gathers a victim's personal details through phishing, a data breach, or a bribed employee, then persuades or pays a telecom worker to transfer the victim's number to a SIM the attacker controls; once the transfer succeeds the victim's phone loses service and the attacker begins receiving the one time passcodes needed to reset passwords and drain financial or cryptocurrency accounts. The United States FBI recorded 1,600 SIM swapping complaints in 2021, an increase of more than 400 percent from 2018, with reported losses of 68 million dollars that year against 12 million dollars combined for 2018 through 2020.