• Registered: 2009-09-10
  • Posts: 21

Topic: Successful login on key B with readable key B

According mifare documentation, if trailer is configured with key B readable any autentication to this sector with key B will not work. I made trailer KeyA: 010101010101 and KeyB: FFFFFFFFFFFFF
block value: 010101010101FF078069FFFFFFFFFFFFF to trailer sector and after readback I get: 000000000000FF078069FFFFFFFFFFFFF (key A is masked, key B is readable). I can read whole sector with autentication on key A (01.....01) OR on key B (FF...FF). I think this is against specification, but I may be wrong. If it is not, maybe my cards are fake/counterfeit?

  • roel
  • Administrator
  • Offline
  • Registered: 2008-05-21
  • Posts: 246

Re: Successful login on key B with readable key B

From the datasheet wink

[1] if Key B may be read in the corresponding Sector Trailer it cannot serve for authentication (all grey marked
lines in previous table). Consequences: If the reader tries to authenticate any block of a sector with key B
using grey marked access conditions, the card will refuse any subsequent memory access after
authentication.

authenticate - yes
read/write - no

  • Registered: 2009-09-10
  • Posts: 21

Re: Successful login on key B with readable key B

roel wrote:

authenticate - yes
read/write - no

It is not still not clear for me. In my card, if I log into card (with sector trailer as described above) using key B and I can read sector (any block) (after authentication with key B) it is my misunderstood (I think it should fail) or something wrong with my card?