> Credit card numbers or passwords that are stored in an unsalted hash What's the purpose of hashing a credit card number? For passwords, please use a proper K

> Credit card numbers or passwords that are stored in an unsalted hash What's the purpose of hashing a credit card number? For passwords, please use a proper KDF instead of reinventing salted password hashing. While it's widely known not to build your own crypto, most people still write stuff like sha256(sha256(password) + salt).