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How to Decrypt a PIN
You can use the EncryptionDecryptionTool.html to decrypt the PIN, assuming your K100 was injected with a key whose BDK value you know (such as the standard test key: 0123456789ABCDEFFEDCBA9876543210).
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For more about PIN encryption, see https://en.wikipedia.org/wiki/ISO_9564#PIN_encryption. This describes ISO-9564, the relevant industry standard.
NOTE: In this ID TECH document, Jane Xu explains that when a PAN is less than 16 digits long, it gets zero-padded on the left for purposes of PIN recovery. When the PAN is more than 16 digits, only the rightmost 16 digits are used.
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