New Economy; A security researcher outlines a low-technology approach to using cyberspace to create havoc in the real world.
By John Schwartz
Published: April 14, 2003
WHAT'S virtual is virtual, and what's real is real. Right?
Most experts think of cyberattack as something that will happen in the virtual world, with effects on, say, computer networks or access to bank accounts. Cyberattacks involving the use of online tools against the offline world would be much harder.
But a recent paper by a computer security researcher at Johns Hopkins University suggests that there are plenty of gateways that connect the cyberworld with the more familiar terrain that some call ''meatspace.'' And, since he is a security researcher, he does it by showing the potential for a cunning attack that crosses that gateway.
Aviel D. Rubin, the technical director of the Information Security Institute at Johns Hopkins University, describes in the paper with two co-authors a real-world attack that uses computers to automate tasks and the power of the Internet to disseminate information.
Using tools that have been published by search engines like Google that allow programmers to automate searches on a large scale, Mr. Rubin and his colleagues described a relatively simple program that could set the victim up to receive catalogs from hundreds of thousands of Web sites that have sign-up forms.
In fact, something like what Mr. Rubin describes has already happened. Last year, Alan Ralsky, a spam-sending entrepreneur known as the ''spam king,'' gave an interview to The Detroit Free Press boasting about his 8,000-square-foot house and all the money he made from sending unwanted e-mail to hundreds of millions of people at a time. Shortly after that article appeared on Slashdot.org, a major online news source for technophiles, its readers signed Mr. Ralsky up for thousands of catalogs, brochures and more. Soon he was getting hundreds of pounds of mail every day.
That was a spontaneous effort by a large community. But Mr. Rubin's paper suggests that anyone can get a computer to stand in for the Slashdotters and bury someone in junk. And Google shows hundreds of thousands of Web pages from which anyone could request a catalog.
It sounds like a new version of the oldest prank in the book -- the cyberspace equivalent of the old order-50-pizzas-for-your-enemies trick. But it's much bigger than that. Mr. Rubin's attack could be enormously disruptive to the target, and could paralyze the local post office that has to deal with the onslaught. As the report notes, the exploit could be used as a diversion to accompany a deadly terrorist act, like mailing an envelope containing anthrax spores.
Some experts have talked about hypothetical, sophisticated cyberattacks on real-world facilities that are connected to the Internet, like the power grid and dams. But the situation described by Mr. Rubin suggests that a far more low-technology approach could cross the barrier between virtual and real realms.
Other automated attacks could easily follow, he said in an interview, including automated orders for hundreds of maintenance requests, package pick-ups and service calls.
Why risk unleashing such mischief by writing about it? That's always the question security researchers face, and Mr. Rubin said that he would never have released the paper if he thought that the attack would not emerge otherwise, or if there were no way to stop it. But the programming tools are out there, he said, and sites are vulnerable. It's only a matter of time before the ''script kiddies'' who start cyberattacks from code that others develop and share start trying to bury people in paper. ''If we knew about it and did nothing, and then the attack was launched, we would be guilty of negligence,'' he wrote. ''It is our judgment that the time has come to reveal this threat.''
In the report, he also describes ways that Web sites can make the process of filling out forms hard for automated programs to do, in some cases simply by asking the user to answer an unexpected question or to solve a simple puzzle before proceeding. One of the fathers of computer science, Alan Turing, once suggested that artificial intelligence could be tested by seeing if a program could be good enough to fool a human being into thinking he was communicating with another person.
A ''reverse Turing Test'' -- already in wide use in computer security to foil automated attacks -- would stump a silicon brain while letting people get the information they need without much fuss, he said.
The paper, which can be found at www.avirubin.com/scripted.attacks.pdf, has impressed Bruce Schneier, a security expert who has been looking at these issues. He is writing about it for the latest edition of his widely read newsletter, Crypto-Gram. ''This interstitial area where cyberspace meets the real world is a ripe area of attack,'' he said in an interview. He sees this problem as being the real-world equivalent of a distributed ''denial of service'' attack, in which the attacker gets computers around the world to inundate a target machine with data, messages and other electronic detritus that make it impossible for legitimate users to get through to it.
A spokeswoman for the Postal Service, Sue Brennan, said the attack described by Mr. Rubin might not work in practice. ''The concepts in the document, while compelling, appear to be systematically flawed with regard to the controls our major mailers would have in place to prevent such an event from occurring,'' she said.
''That's good,'' Mr. Rubin said, but he argued that an attack that ordered only one catalog from thousands of sources might have serious effects before it could be detected. ''I hope she's right,'' he said. But he did not sound optimistic.
Drawing (Igor Kopelnitsky)