THC-SmartBrute - Finds undocumented and secret commands implemented in a smartcard

Monday, December 8, 2014

This tool finds undocumented and secret commands implemented in a smartcard. An instruction is divided into Class (CLA), Instruction-Number (INS) and the parameters or arguments P1, P2, P3. THC-SMARTBRUTE iterates through all the possible values of CLA and INS to find a valid combination.

Furthermore it tries to find out what parameters are valid for a given class and instruction number.


You need a PC/SC compatible smartcard reader that is supported by the PCSC-LITE library.
A list of supported devices can be found here
THC-SMARTBRUTE was developped with the XXX smartcard reader.

Command line arguments
        prints a lot of debugging messages to stderr *FIXME*
        only prints found instruction if its not element of the standard
        instruction list
        before iterating through all possible combinates of class and
        instruction-number typical class/instruction-values are verified for
        After that the classes 0x00, 0x80 and 0xA0 (GSM) are tried first.
        prints out the usage
--chv1 pin1
        a VERIFY CHV1 instruction with pin1 as argument is executed
--chv2 pin2
        a VERIFY CHV2 instruction with pin2 as argument is executed

        finds valid parameter p1 and p2 combinations for the instruction
        the user defined with --cla and --ins .
        For parameter p1 the value 0x00 is assumed.

        find valid p3 values for given --cla, --ins, --p1 and --p2

--cla CLASS
        sets the instruction class to CLASS
--ins INS
        sets the instruction-number to INS
--p1 P1
        sets parameter p1 to P1
--p2 P2
        sets parameter p2 to P2
--p3 P3
        sets parameter p3 to P3

1. ~$ ./thc-smartbrute
        run thcsmartbrute without any arguments to brute force for valid instructions
2. ~$ ./thc-smartbrute --undoconly
        find valid instructions but only print out non-standard instructions

3. ~$ ./thc-smartbrute --cla 0xA0 --ins 0xA4 --brutep1p2
        find the first two arguments for the GSM instruction SELECT FILE

4. ~$ ./thc-smartbrute --cla 0xA0 --ins 0xA4 --p1 0x00 --p2 0x00 --brutep3
        find the 3rd argument for the already found first two arguments 
        for the GSM instruction SELECT FILE

Subscribe via e-mail for updates!