High-tech thieves have discovered a way to drain funds from mobile wallets, even when the iPhone is locked. The only limit on a victim's potential loss is the amount of money in the account linked to the phone. The scam, first exposed in 2021, only affects iPhones that are in Express Transit mode and linked to a Visa card. No other major credit card is susceptible to the stealth theft. However, Samsung phone users are not vulnerable as the hack does not work with Samsung Pay. The trickiest way to avoid the scam is to tap on a thief's NFC card reader, which transmutes the owner's payment data to a second phone via a laptop.