Re: Why PCI-DSS doesn't address Ram Scraper?
Reading memory from other processes requires a program running with full administrator rights. If the bad guys have already obtained that level of access to the POS system, it's game over anyway. By definition, the attackers have gained the ability to perform any operation on that machine. The entire system, and any data passed to it, is compromised, no matter what you do.
That said, I think you're right, the key here is separation, but i think the emphasis needs to be on separation of the POS system from the outside world. Why are POS terminals openly networked, with active internet connections? It's cheaper, easier to develop software for, and easier to administer. It's also incredibly vulnerable to attack. POS systems shouldn't have any means to communicate with each other or the outside world. They should have a single secured and encrypted point of communication with a central server of some kind where required, and other than that, they should be completely isolated.
At the end of the day, if an attacker can engineer a situation where he can gain unsupervised physical access to a POS terminal, he will be able to compromise it. That should be where it stops though. It shouldn't be possible for an infection to spread from one POS system to another, or for data from a compromised POS system to be leaked back over the internet. If attacks were limited to individual terminals, and recovering data required physical access, or additional hardware to be dropped in like a phone, it would greatly increase the difficulty and reduce the payoff for the bad guys, and they'll go back to targetting ATMs or the like where they also need physical access, but the payoff is bigger.
In terms of physical security too, why are POS systems often sitting on an open shelf right next to customers and employees, with exposed USB ports and no real physical isolation? Again, because it's cheaper and easier, but it's very insecure. POS systems should be viewed as filled to the top with cold hard cash, and secured accordingly.
POS systems could learn a lot from ATM security. Any software platform will have vulnerabilities just waiting to be discovered, and where there's a lot of money involved, the bad guys will find them. Network isolation and restricted physical access are key. When was the last time you heard about a network of thousands of ATMs being hacked? That's because they're heavily network isolated. The PCs themselves can be attacked if you can gain physical access, which is why they're supposed to be kept under lock and key in a safe. If the bad guys don't have to get a blowtorch out to compromise your POS system, you're doing it wrong.
User Rank: Strategist
7/25/2014 | 9:50:07 AM