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'Alan Mushing sprays a sample magnetic stripe with a fluid suspension of iron filings – instantly showing up the patterns of zeroes and ones on the card as a series of light and dark bands.' -- That sounds very interesting, i've not heard of anyone doing that before, would you then need an optical microscope to see the patterns I wonder?

Edit: http://www.tetherdcow.com/another-science-experiment/ Has a nice photo of the trick

I just tried some magnetic viewing film I bought a while ago, to see if you can see any lines from a credit card with them, but alas that didn't work.

I've done this! You can see them with the naked eye quite easily. Just shine a light diagonally at the surface. I wouldn't bother reading them by hand though. You could take a photo of it with a digital camera then post-process it and stick it through mathematica or something.

However you might as well just use a card reader.

I used to hack stored value phone cards back in the very early 1990s. First they had an optical system which was easily circumventable with a torch a knife and some epoxy glue. Then there were the smart card ones which were easy to hack by scratching off the programming voltage pad on the card.

I got to the later mag strip cards like this and couldn't be bothered any more.

Neat :) Yeah I was thinking you could write an algorithm to process the image of the credit card to data.

What do you mean by "they had an optical system which was easily circumventable with a torch a knife and some epoxy" out of interest?

Well they were pretty crap. There was a metalised bit of plastic for the card and the reader burned certain bits of the plastic to gate the light. If you bought a £5 card you could cut a hole in it, fill it up with epoxy and use a permanent marker to fool it into thinking you had a £20 card :)

Edit: my memory is faulty; they were units, not £. Been a long time :)

Probably won't matter. There's been numerous, even cheap, solutions to the card fraud problem devised in academia and industry. There's companies trying to sell a variety of them. The issue is that the bank's don't really care so long as the cost to them stays under a certain amount. Their strategy, instead of securing cards, is to push liability onto the cardholder using any legal means possible. Their most successful trick has been lobbying politicians to keep liability away from them.

So, we're not going to see improvements unless (a) they're willing to sacrifice significant profit to protect consumers' money, (b) politicians force them to, or (c) courts rule clearly enough against them enough times to force them to. The first two are highly unlikely. The third is beginning a bit with some rulings, esp in ACH. Not holding my breath: just assume the CC's will be compromised, esp if someone takes physical possession of it. I know people that exclusively use cash or pre-paid cards for this reason: main card or bank account doesn't get hit.

The PAN on smart card based chips is clear text readable with a simple USB reader use EMV mode https://code.google.com/p/cardpeek/

Simple CCD cameras will read out PAN+CCV without even having to use a smart card reader.