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moebius

Contributor

Registered: 2011-03-10

Posts: 206

Understanding Access Condition Bytes

Hello! Can someone explain by using some examples, the access condition bytes being used in Mifare's 1K cards?

Thanks!

Last edited by moebius (2011-04-11 19:16:14)

moebius

Contributor

Registered: 2011-03-10

Posts: 206

Re: Understanding Access Condition Bytes

Hello! Can someone explain by using some examples, the access condition bytes being used in Mifare's 1K cards?

Thanks!

Answering myself

Using ACS Mifare Key Management Tool I was able to understand and analyze options bits in Mifare Cards really easy.

Hope that helps to someone else.

vivat

Contributor

Registered: 2010-10-26

Posts: 332

Re: Understanding Access Condition Bytes

I cannot understand what this bytes mean:
(data from Sector 1, Sector trailer 3, block 7)

data:00 00 00 00 00 00 70 f7 88 69 00 00 00 00 00 00

first and last 12 hex symbols are keys A&B, they are masked as zeros
I tried to google but didn't found this tool, can you upload it?

moebius

Contributor

Registered: 2011-03-10

Posts: 206

Re: Understanding Access Condition Bytes

I cannot understand what this bytes mean:
(data from Sector 1, Sector trailer 3, block 7)

data:00 00 00 00 00 00 70 f7 88 69 00 00 00 00 00 00

first and last 12 hex symbols are keys A&B, they are masked as zeros
I tried to google but didn't found this tool, can you upload it?

http://www.m3g4upl04d.com/?d=SWLNVC4E

here you are.

maybe someone can write an open source version

vivat

Contributor

Registered: 2010-10-26

Posts: 332

Re: Understanding Access Condition Bytes

WTF did you uploaded? It has Trojan-Downloader.Win32.Banload inside:
http://www.virustotal.com/file-scan/rep … 1318615227
I will try to run it on isolated VM

Last edited by vivat (2011-10-14 19:16:11)

vivat

Contributor

Registered: 2010-10-26

Posts: 332

Re: Understanding Access Condition Bytes

Launched on the VM, works OK
thanks, moebius

moebius

Contributor

Registered: 2011-03-10

Posts: 206

Re: Understanding Access Condition Bytes

No problem amigo! It's not a Trojan! If you have time to write some open source program to mimic its behavior, will be appretiated!