:: Deepquest ::

What’s more common than an ATM? Almost every day people use those to get fast cash. I was wondering for the past months how it works. Basicly it’s just a computer, stuck in a small bunker with with 2 holes, 1 for cash, 1 for the credit card and a numeric keyboard.

Well I started to wonder few months ago, when I heard that the [url=http://deepquest.code511.com/blog/comments.php?id=P11_0_1_0_C]virus slammer[/url] hit some [url=http://securityfocus.com/news/2164]ATMs[/url], it’s now the turn of a new worm [url=http://www.theregister.co.uk/content/55/34175.html] named Nachi[/url]. I think it’s quiet scarry to imagine this, a virus affecting an ATM!!?? The little grey box where you put you credit card, and where in secret you type you pin code.
Does it mean ATMs are not safe? Does it means my bank doesn’t protect properly my account?
Well after few months of investigation I’d say hell yeah! Don’t trust ATMs
I started to read, lurn more about the cards mecanism and ATMs. The first paper I found [url=http://deepquest.code511.com/blog/images/uploads/txt/scsecurity.pdf]was wrotten by Stefano Zanero[/url], a nice paper about smart cards content security. The concept is easy the only way to interact with ATM are the 2 possible imput (the card and the keyboard), my initial idea is NOT to get “free” cash but to shut it down. Most ATM I saw in europe was running ms-dos or OS/2 or even some a derivitive of windows XP. Commun brands found of ATM are IBM, NCR or even Siemens. The other thing I also discovered is that those machines are in fact very small. For exemple the current ATM run only a pentium 500 mhz with 32mo, but you’ll see also some 486dx2/66 cpu.

Humm… x86 ? X86=assembly=evil code. Of the communication side nothing complex, either a network card or modem. It looks like that for eg in Thailand:

Anyway let’s get back to the main point: shutdown that ATM for fun and non-profit. What you need is few blank smart card with magnetic strip and chipset you can fine some on ebay for less than 10 box. You’ll also need a read/write reader for both side (magnetic and chipset) such as [url=http://www.ute.com/products/msr206.html]MSR206[/url] this one is magnetic track only.
What to write on the card? Than the big part, I can’t give much details for reasons you can imagine. The concept is to flood the ATM with specialy crafted requests for x86, because of the low ressources of the ATM it will crash.
It took only few seconds to fully DOS it:

and

Conclusion:
don’t trust ATMs, banks doesn’t seems like taking seriously the past security issues. How to get your cash? Don’t you have a bank, that what they are supposed to do: give you cash when you have some;-)