Reader-answer transfer error spam

[lesterCrest6]

Hi all,
I have tried to perform a harnested attack on a Mifare Plus 2k Card. As soon as the attack begins I am spammed by the following message: Reader-answer transfer error, exiting..

I am using a SCL3771 USB NFC reader on Kali Linux. Any suggestions?

Thanks!

[tsabicheck]

I got the same for a 4K card (reported by mfoc).

• MIFARE Classic 4K
• MIFARE Plus (7 Byte UID) 4K, Security level 1

The interesting thing is if I try with a sector which has a known KeyA, it can collect nonces and find KeyB. However if I try with a block where none of the keys are known, I get the error.

Sector 0 (known KeyA)

$ libnfc_crypto1_crack a0a1a2a3a4a5 0 A 0 B
Found tag with uid 8axxxx80, collecting nonces for key B of block 0 (sector 0) using known key A a0a1a2a3a4a5 for block 0 (sector 0)
Collected 83 nonces... ^C

But for Sector 1 (none of the keys are known)

$ libnfc_crypto1_crack a0a1a2a3a4a5 0 A 4 A
Reader-answer transfer error, exiting.. Some other error occurred.
Found tag with uid 8axxxx80, collecting nonces for key A of block 4 (sector 1) using known key A a0a1a2a3a4a5 for block 0 (sector 0)
Reader-answer transfer error, exiting.. Reader-answer transfer error, exiting.. Reader-answer transfer error, exiting.. Reader-answer transfer error, exiting.. Reader-answer transfer error, exiting.. Reader-answer transfer error, exiting.. ^C

Do those sectors have an improved security? Or anything to do differently?