mastercard emv decrypt software download

Once we’ve got the derived key, we’ll talk about how to transform it into a Data, PIN, or MAC variant, which is relatively easy. Let’s go ahead and see what’s involved in obtaining the “derived key” (step 2), since this is by far the most painstaking part of the 3-step process. (Note that while most credit card readers are set up to use the Data variant key for the transaction session key, some are, in fact, set up to use the PIN variant instead.)

Convert the derived key of Step 2 into your choice of Data Key, PIN Key, or MAC Key. Use the ANSI X9.24 (DUKPT) key-derivation algorithm to derive a basis key, or initial “derived key,” from the KSN and IPEK.ģ. (See Part I of this article for details on how to do this.)Ģ. (One BDK can be the source of many unique IPEKs.) If you don’t know the IPEK for your device (and there’s no reason why you would, since the IPEK is never written down anywhere), you can derive it from a KSN and a Base Derivation Key, using the technique described in Part I of this article.ĭeriving a session key (sometimes called a working key, or simply “data key”) is actually best thought of as a 3-step process.

Unlike the BDK, the IPEK is unique to a given physical device. The IPEK, in turn, is derived from a super-secret key (that’s never injected into a card reader) called the BDK (Base Derivation Key). The question is: How can you derive a DUKPT key that will unlock a given transaction? The answer is: Generally speaking, you need the Key Serial Number (KSN) for the transaction, plus a special value called the IPEK, or initial key that was injected into the credit card reader. The key can’t be reused for any other transaction(s) hence, replay attacks are impossible. These days, almost all credit-card data gets encrypted using a one-time-only key, obtained via a special key-management scheme called DUKPT (which stands for Derived Unique Key Per Transaction). It’s important to understand that in the DUKPT world, every transaction has its own key. Then you can decrypt the data using the key. The answer: You need to know the algorithm that was used to encrypt the data, and the keythat was used. Customers often ask: How can I decrypt the data coming out of my ID TECH credit-card reader?

Mastercard emv decrypt software download