Ultrasonic fingerprint sensors like the one on the Galaxy S10 offer improvements over optical fingerprint sensors, like speedier unlocked and being more secure. That doesn't mean that they're perfect, though.
The Samsung Galaxy S10's in-display ultrasonic fingerprint sensor has been fooled by a 3D print of a fingerprint. User darkshark explained their process in an imgur post, saying that they took a photo of their fingerprint on the side of a wine glass, imported the image into Photoshop, and made a few tweaks like increasing the contrast. They then created a 3D model of the fingerprint and printed that out using a 3D printer, which took about 13 minutes.
In a video, darkshark can be seen placing the 3D-printed fingerprint onto the screen of a Galaxy S10+ and unlocking the device. darkshark says that it took them three tries to get the 3D-printed fingerprint just right, but that they were able to unlock the phone.
"If I steal someone's phone, their fingerprints are already on it. I can do this entire process in less than 3 minutes and remotely start the 3d print so that it's done by the time I get to it," says darkshark. "Most banking apps only require fingerprint authentication so I could have all of your info and spend your money in less than 15 minutes if your phone is secured by fingerprint alone."
Whenever a device comes out with a relatively new security feature, one of the first things that happens is some people try to beat that security, and so it's no surprise to see the same thing happen with the Galaxy S10. While most folks won't ever have anything like this happen to them, it's a good reminder to have extra security on your accounts and keep tabs on your important information, just in case someone does get your phone and manages to break into it.