Just one day after airing an ad that got a lot of attention during the Super Bowl, T-Mobile caught even more attention with a semi-confusing text to customers on Monday, warning of an industry-wide phone number port out scam.

According to Lorenzo Franceschi-Bicchierai’s article in Motherboard, this type of cyberattack is also known as SIM hijacking. The scam is a fairly easy and effective inroad for hackers that can lead to valuable data. The way it works is that a hacker will contact a cell phone provider, pretending to be the true cell phone owner. Then, the hacker requests a new SIM card for the victim’s phone number.

“Once the provider issues the new SIM, the scammer can take over the victim’s phone number and then move on to other targets that are linked to it, such as social media or banking accounts. Once the hacker has control of the phone, they can use it to reset the bank password by asking the bank to send a reset link via text, for example,” writes Franceschi-Bicchierai.

Read the full story at Motherboard.