SCADA Systems: Achilles Heel of Critical Infrastructure

Our critical infrastructure is an attractive target for enemy nations, terrorist groups, or even run-of-the-mill cyber criminals, and many security experts believe that it is not remotely protected against cyber attacks. The SCADA systems that manage and control much of the critical infrastructure for the United States were not designed with security in mind, and are not engineered for an Internet-connected world.

SCADA systems are uniquely enticing because a successful attack could cripple a nation. The Stuxnet worm that targeted nuclear power capabilities in Iran contained a rootkit that could hijack the control and behavior of PLC (programmable logic controller) devices used for plant operations.

In a Wall Street Journal article Richard Clarke, former White House advisor on cyber security, warns that there is evidence that China has been actively probing and hacking the United States power grid. Clarke points out, “The only point to penetrating the grid’s controls is to counter American military superiority by threatening to damage the underpinning of the U.S. economy. Chinese military strategists have written about how in this way a nation like China could gain an equal footing with the militarily superior United States.”

Dr. Avishai, CTO of AlgoSec, recently discussed some of the challenges facing SCADA systems. Avishai notes, “In the old days, we worked with an ‘isolated network’ assumption. The network operated with very simple communication protocols and over serial lines.”

Avishai explains that SCADA networks were not designed with security in mind and can not differentiate between legitimate requests and malicious responses. SCADA systems were traditionally on isolated networks that would require an attacker to first gain physical access to the target facility.

“Hacking SCADA systems no longer requires physical access, just a network connection, a way to route packets to the logic controller and a way to bypass the traffic filters, which are all activities that hackers understand,” proclaims Avishai.

Randy Abrams, director of technical education at ESET, agrees that SCADA systems have their weaknesses, but feels that the humans behind the networks, and social engineering attacks are the real weak point.

There are two very significant human factors that come into play according to Abrams.The first follows the points made by Dr. Avishai–the false assumption that SCADA systems are somehow protected because they’re not connected to the Internet. The false belief in security by obscurity leaves these systems exposed to risk.

“The other human factor is social engineering,” says Abrams. “We have seen countless spear-phishing attacks that have resulted in compromise of military and private industry systems. The recent disclosure of a spear-phishing attack against high ranking US and south Korean officials, as well as journalists and dissidents that resulted in people divulging the passwords to their Gmail accounts demonstrates how incredibly little people understand about the nature of phishing attacks and social engineering in general.”

The critical infrastructure is called that for a reason–it is the infrastructure that is essential for our society and economy to function. Combine the security flaws inherent in the SCADA systems themselves, with the with weaknesses in human nature and vulnerability to social engineering attacks, and you have a potential recipe for disaster.