ONR system would protect ships from Stuxnet-like attack

RHIMES would limit the scope of any attack by giving electromechanical controllers slightly different programming.

Navy ship radio system

In terms of cyber defense, the military has talked a lot recently about the need to protect infrastructure, particularly with regard to such things as power grids, water plants and nuclear facilities. But for the Navy, infrastructure also means ships, whose networked mechanical systems—a floating Internet of Things—are essential to operations.

In order to protect those systems from potentially disabling cyber attacks, the Navy is developing an innovative shipboard cyber protection system called RHIMES, for Resilient Hull, Mechanical, and Electrical Security, designed to not only to protect ships’ systems but to mix up the profiles of their controllers to prevent any single attack from working against more than one of them.

“The purpose of RHIMES is to enable us to fight through a cyber attack,” Rear Adm. Mat Winter, chief of Naval Research, said in a release. “This technology will help the Navy protect its shipboard physical systems, but it may also have important applications to protecting our nation’s physical infrastructure.”

As the Office of Naval Research points out, antivirus and other security software works against known threats. When new threats appear, new patches are written and, if diligently applied by system administrators, systems can stay fairly safe. But they’re still vulnerable to zero-day attacks—new exploits that haven’t shown up before—or at times even slight tweaks to a known virus or worm.

RHIMES, on the other hand, “relies on advanced cyber resiliency techniques to introduce diversity and stop entire classes of attacks at once,” said Dr. Ryan Craven, a program officer the Cyber Security and Complex Software Systems Program in ONR’s Mathematics Computer and Information Sciences Division.

That diversity is key to RHIMES’ approach. Electromechanical systems are operated by programmable logic controllers, which are embedded computers that automate functions. They generally are isolated from the Internet, but they can be hacked by, for instance, a virus introduced via a thumb drive.

The most famous example is the Stuxnet hack reportedly by the United States and Israel (and introduced via thumb drive), of PLCs in the centrifuges of an Iranian nuclear enrichment facility. Last year, a similar attack at a German steel mill caused extensive damage by overheating the blast furnace and preventing workers from shutting it down. And in 2011, researchers showed how a Stuxnet-style attack could wreak havoc at prisons by attacking the PLCs that control doors and security camera systems.

Most controllers, as well as their backups, have the same core programming, Craven said, so the ability to compromise one means the ability to compromise them all. RHIMES counters that potential predicament by introducing “a slightly different implementation for each controller’s program,” he said. “In the event of a cyber attack, RHIMES makes it so that a different hack is required to exploit each controller. The same exact exploit can’t be used against more than one controller.”

The system would provide the kind of resiliency necessary to withstand an attack by limited any successful exploit to one controller. Along with protecting the Navy’s ships, RHIMES’ approach could eventually have benefits for all kinds of infrastructure, from transportation systems and power plants to hospitals, both military and civilian.

“Vulnerabilities exist wherever computing intersects with the physical world, such as in factories, cars and aircraft,” Craven said, “and these vulnerabilities could potentially benefit from the same techniques for cyber resilience.”