Hacking this this card chip

[king.oslo]

Hello there,

In our house we have a washing machine system that holds information about how many times you have washed your clothes compared to a total number of times you are allowed.

I have seen these kinds of chips on all sorts of things, mobile sim cards, credit cards etc. I expect they have a security system built in.

The question is: how do one hack these guys? I am not a criminal, so I would not hack credit card, but it would be fun to experiment with something as harmless as these washing machine cards! How can I retrieve the info on them, and overwrite the data?

There are probably lots of information about the subject, but I don't know where to look for it, or what to look for!

Thanks!M

 

[Nigel Goodwin]

A basic non-encrypted (the only type that should be discussed here) card is usually just a simple EEPROM, such as a 24C16 - you would need to consult the card's datasheet.

 

[picbits]

I did a similar project many years ago when the company I was IT Manager for introduced a pay as you go card operated coffee machine. You could preload the cards with credit then use them over the week to buy your coffee with. The staff were given a card with credit on each week (or month - I can't remember) but when the credit was used you'd have to top them back up.

One of the problems was that occasionally your card would become corrupted and the machine would refuse to read it.

I bought a card reader from Bull Electrical in the UK and found the chip onboard was just a simple eeprom. Better than that, all the cards had the same data on - there were no serial numbers or encryption

I took a dump off a new card and was about to try and hack it when I realised I didn't need to - when my card was empty, I'd just reload the virgin data on which was stored on my PC.

I never paid for a drink in that company again

 

[ronv]

I have a similar thing on a little key that lets me buy golf balls at the driving range. Must be simple cause they can refill it in the shop.

 

[picbits]

Is it a multicontact device Ron or an Ibutton type device (2 wires) ?

If its multicontact it could be worth seeing if its a standard eeprom - if its a 2 wire device then it may be very very very secure ......

 

[ronv]

It's multi contact. Almost the same layout as posted here. It would be fun to hack it. Not nice, but fun.

 

[king.oslo]

I loved your story picbits. What do you reckon guys, how do I best proceed to hack it?

This image is just one I found on the internet for a random chip, but it has the same number of contacts as my circuit:
**broken link removed**

On C2, i got 2.8V when I connected 3.3VDC and GND to C1 and C5. I don't know if this is useful information. I have a Bus Pirate. Should I try and connect it somehow and use I2C standard on C3 and C7, or something else?

Marius

 

[king.oslo]

I found this **broken link removed** this looks just like my chip! Compare the photographs if you want as well! What are your thoughts?

 

[king.oslo]

Bump! M

 

[Nigel Goodwin]

Bump! M

What's to bump?.

Do you have the manufacturers datasheet for your specific card? - if not you'll completely in the dark. Cards can have EEPROM, or EEPROM and a processor, of various types. It's fairly pointless posting pictures of the connector, as it's a entirely standard interface.

 

[sanjubluerock3]

buy a sim card reader or build one ....

https://www.ladyada.net/make/simreader/download.html

video link

https://vimeo.com/1362948

 

[picbits]

As Nigel said - we've reached about as far as we can go without more information.

If you've nothing to lose if you kill the card, look up how to interface to a standard 24c or similar eeprom and give it a go.