Researchers at the University of Cambridge in England have invalidated the security systems in many smart card systems by developing a way of attacking and causing faults in cards using common tools such as a photographer's flash gun and a microscope.
Ross Anderson of Cambridge University's Computer Laboratory described the discovery, by doctoral candidate Sergei Skorobogatov, at the Institute of Electrical and Electronics Engineers Inc. Symposium on Security and Privacy in Oakland, California, on Monday.
This method is much simpler and more effective than the techniques used in the past, the researchers said in a statement. While many security processors can stop the more basic attacks, they will now have to be upgraded, it said.
Simply shielding the processor by adding, for example, a top metal layer to the chip is no longer enough, because silicon becomes transparent to the light in an infrared flash and the chip can therefore be attacked from the rear. Electromagnetic pulses and X-rays could also be used, the researchers said in their statement.
The attack technique was kept under wraps for a year until defensive technologies could be developed. A new silicon technology has now been discovered that can block this and many of the previously known attacks, they said.
Cambridge Laboratory's team has to look at both sides of the smart card security battle, said Simon Moore, another of the team's researchers, on Tuesday. "(We try) to design better smart cards using better techniques and circuit designs, but we also look at how to break them. It's like being a good locksmith -- you have to know how to pick locks," he said.
Cambridge Laboratory has been working with the European smart card industry to improve security, Moore said.
The idea for the new attacks came from reading reports about work on older chips and wondering how sensitive the new opaque plastic packaging used on most current smart cards would be, he said.
"We want the public to be wary of these technologies because while they have appropriate uses, such as for SIM (Subscriber Identity Module) cards, (there is talk of using them) as national identity cards. That's of great concern because there is then the potential to clone these cards and create fake ones. A fake SIM card may not cause a great personal cost to the person who loses it, but a fake passport could almost ruin their life."