> "While basic security measures were implemented, in that customers were told to input card numbers using the handset, the unique audio tones generated by pressing keypad buttons would make it straightforward to recover the 16-digit number and expiry date."

and in the original:

"Instead of saying their card number and three-digit security number, customers type them into the keypad – protecting the most serious financial information."

We should produce a DTMF blockchain, seems like the best security out there. /s On a more serious note: Are regular people/journalists not aware of how pressing buttons on a phone works anymore?