Mifare Classic: Card Recovery Tool
You might ask: "Why not just throw away the old MIFARE Classic?" Because critical infrastructure is slow to upgrade.
This exploit takes advantage of the fact that once you have one key (often a default factory key like FFFFFFFFFFFF ), you can use the information from that authentication to "peek" at and recover the keys for all other sectors on the card. Modern-Day Tools: From Lab to Pocket mifare classic card recovery tool