[4] mfoc – MIFARE Classic Offline Cracker. GitHub: nfc-tools/mfoc.
What is your ? (e.g., recovering data from a corrupted card, creating a backup, auditing system security)
mfoc -O card_dump.mfd
Recovering or rewriting the unique identifier (UID) on special "Magic" cards to match an old, non-functional badge. Key Tools for MIFARE Classic Recovery mifare classic card recovery tool
MIFARE Classic is susceptible to various attacks (such as the "DarkSide" or "Nested" attacks) because of its weak proprietary CRYPTO1 algorithm. Intended Use:
Once you possess the backup_dump.bin file, you can write the data back to a replacement card if the original card is physically damaged.
If the sector trailer (Sector 0) is destroyed, you may need a "Magic Card" (Gen1 or Gen2) to rewrite the UID and restore the sector structure. Handling "Hardened" or "Locked" Cards [4] mfoc – MIFARE Classic Offline Cracker
The Proxmark3 is the gold standard for RFID research and recovery. It is a highly capable dedicated hardware device that can sniff, emulate, and clone RFID signals across both low (125 kHz) and high (13.56 MHz) frequencies.
You do not always need dedicated hacking hardware. A standard Android smartphone with an integrated NFC chip can act as a basic recovery tool.
Is the card showing or is it completely dead? Do you have an Android phone , Flipper Zero , or Proxmark3 available? If the sector trailer (Sector 0) is destroyed,
The software will authenticate with the known key, exploit the nested vulnerability, and systematically crack the remaining sectors.
mfcuk -C -R 0:A -R 1:A -R 2:A ... -v 2
Are you encountering when scanning the card?
MFOC‑Hardnested will first attempt to authenticate with default keys. If that succeeds, it will proceed with the nested attack. If the card is resistant to the nested attack, it will fall back to the hardnested method.