:max_bytes(150000):strip_icc():saturation(0.2):brightness(10):contrast(5)/ChipCard-eda854c8b7c94028a2a18a2a9d03396a.jpeg "emv chip writer dynamic clone")
Secondly, the number of significant UN digits is determined by the card.
#Emv chip writer dynamic clone code
However, there are some weaknesses in the specification of this.įirstly, the specification restricts the UN to the encoding of numbers, namely the Binary Decimal Code (BCD), which essentially means that if we look at such an encoded number in HEX, we will only see numbers from 0 to 9, all other values are considered as if forbidden. For the attack, the UN strongly interferes with us, since it is not possible to enumerate 4 bytes without going beyond the limits of the transaction counter. Unpredictable Number prevents the generation of authentication codes on a real card for subsequent use in fraudulent transactions. At the same time, to generate the signature, the POS terminal informs the UN (Unpredictable Number) card – 4 bytes, which is also used in the generation of the signature. The signature contains ATC values - 2 bytes, CVC3 (Track1) – 2 bytes, CVC3 (Track2) – 2 bytes, which are generated by the card based on a secret key that the issuing bank and transaction counter (ATC) also know.
However, in this signature there is no signature of the transaction itself. In other words, this command is needed so that the card generates a certain “signature” so that the issuer can verify the card. Thus, the value of CVC3 always depends on the UN and ATC objects. As an argument to the 3DES function, the concatenation of the UDOL data and the transaction counter (Application Transaction Counter, ATC) are used.
#Emv chip writer dynamic clone verification
As a result, the card uses the 3DES algorithm and the secret key to calculate the dynamic value CVC3 (Card Verification Code). The card supports the special COMPUTE CRYPTOGRAPHIC CHECKSUM command, the argument of which is the data defined in the Unpredictable Number Data Object (UDOL). Which means that the card should generate a CVC3 value based on the passed Unpredictable Number. The terminal sends the COMPUTE_CRYPTOGRAPHIC_CHECKSUM command. The card in response sends Track1 and Track2 almost the same as that recorded on the magnetic strip of the card. The terminal sends the READ_RECORDS command. The card answers what type of authentication it supports and whether verification of the cardholder exists there. The terminal sends the GET_PROCESSING_OPTIONS command. In response, he receives the necessary application details. The card sends a list of supported applications. The terminal sends a SELECT PPSE (Proximity Payment System Environment) command. The transaction processing process for contactless cards has been reduced in comparison with chip cards and usually works in the following mode: By the way, Visa cards also have a similar mode of operation – PayWave MSD (Magnetic Stripe Data). MagStripe mode is most likely needed for banks that find it difficult to translate the entire infrastructure to support chip contactless EMV transactions. This mode is implemented on MasterCard cards with a contactless interface. MagStripe is a magnetic stripe card support mode. The version of this protocol supports two operating modes for contactless cards: EMV protocol (MasterCard PayPass M / Chip) and MagStripe (MasterCard PayPass MagStripe) mode. Cloning of a payment card is successful for the kernel version of the EMV Contactless Kernel 2 application. But in the method of the Austrian guys we do not need to know this. In the general case, it is important to keep the PIN code confidential and prevent it from leaking. This is such a scenario in which an attacker steals money from a bank card by reading (copying) information from this card. It is based on a general principle called Skimming. This contactless card attack method was published by two researchers Michael Roland, Josef Langer from the University of Austria. We proceed directly to the principle of cloning.
0 kommentar(er)
