I am trying to clone/write copies of an NFC card. I am using an ACR122U-A9 receiver and running nfc-tools on a kali linux VM.

The card I am trying to clone is identified as a Mifare Classic 1k tag ISO/IEC 14443A (106 kbps), UID SIZE: Double with the use of NFC TOOLS for Desktop and following command:

mfoc -P 500 -O <filename.dmp>

Furthermore, it tells that

Fingerprinting based on MIFARE type Identification Procedure: * MIFARE Classic 1K * MIFARE Plus (7 Byte UID) 2K, Security level 1 and when trying to authenticate it finds that all sectors are encrypted with the default keys.

This should to my understanding make it possible to write copies of the card, but I can't seem to find out how to do it... I have earlier used the


But that currently only supports 4 byte UID's so that is not an option. I believe the authentication where it is used is only on the UID, that is why I 7 byte write UID solution would probably work.

I have also tried to use

nfc-mfclassic W a original.dmp new.dmp

As shown in tutorials like this one https://gist.github.com/alphazo/3303282

But without luck due to an incorrect BCC in MFD file

NFC reader: ACS / ACR122U PICC Interface opened
Found MIFARE Classic card:
ISO/IEC 14443A (106 kbps) target:
    ATQA (SENS_RES): 00  04  
       UID (NFCID1): 01  23  45  67  
      SAK (SEL_RES): 08  
Guessing size: seems to be a 1024-byte card
Sent bits:     50  00  57  cd  
Sent bits:     40 (7 bits)
Received bits: a (4 bits)
Sent bits:     43  
Received bits: 0a  
Writing 64 blocks |!
Error: incorrect BCC in MFD file!
Expecting BCC=12

The card I am trying to dump the data onto is https://www.amazon.com/10pcs-13-56MHz-Changeable-block-writable/dp/B00N4VCJEM

and I believe that the problem might have something to do with the card being the wrong type 4byte instead of 7byte.


According to https://mattionline.de/mifare-classic-1k-clone-block-0-uid/, your problem may be that you do not have a "7 byte UID completely writable mifare classic 1k card". I encountered the same issue, so for me it's off to shopping on the interwebs as well!

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