Paper presented at Financial Cryptography and Data Security. FC 2021 International Workshops.   Added by: Rucknium 6/3/25, 5:31 PM Tabatabaee, S.

Every card comes with it's 4 digit PIN written separately on a piece of paper. If you lose it for any reason, you can mail us your order number and we'll send you the PIN via email. How safe are those cards in reality?

Every card comes with it's 4 digit PIN written separately on a piece of paper. If you lose it for any reason, you can mail us your order number and we'll send you the PIN via email. How safe are those cards in reality?

Every card comes with it's 4 digit PIN written separately on a piece of paper. If you lose it for any reason, you can mail us your order number and we'll send you the PIN via email. How safe are those cards in reality?

Every card comes with it's 4 digit PIN written separately on a piece of paper. If you lose it for any reason, you can mail us your order number and we'll send you the PIN via email. How safe are those cards in reality?

Every card comes with it's 4 digit PIN written separately on a piece of paper. If you lose it for any reason, you can mail us your order number and we'll send you the PIN via email. How safe are those cards in reality?

Every card comes with it's 4 digit PIN written separately on a piece of paper. If you lose it for any reason, you can mail us your order number and we'll send you the PIN via email. How safe are those cards in reality?

Every card comes with it's 4 digit PIN written separately on a piece of paper. If you lose it for any reason, you can mail us your order number and we'll send you the PIN via email. How safe are those cards in reality?

Every card comes with it's 4 digit PIN written separately on a piece of paper. If you lose it for any reason, you can mail us your order number and we'll send you the PIN via email. How safe are those cards in reality?

Every card comes with it's 4 digit PIN written separately on a piece of paper. If you lose it for any reason, you can mail us your order number and we'll send you the PIN via email. How safe are those cards in reality?