Like any other IT environment, there are potential cyber-risks to the International Space Station (ISS), though the station is quite literally like no environment on Earth.
In a session on August 9 at the Aerospace Village within the DEFCON virtual security conference, former NASA astronaut Pamela Melroy outlined the cybersecurity lessons learned from human spaceflight and what still remains a risk. Melroy flew on two space shuttle missions during her tenure at NASA and visited ISS. Hurtling high above the Earth, ISS is loaded full of computing systems designed to control the station, conduct experiments and communicate with the ground.
“Space is incredibly important in our daily lives,” Melroy said.
She noted that GPS, weather tracking and communications are reliant on space-based technology. In Melroy’s view, the space industry has had somewhat of a complacent attitude about satellite security, because physical access was basically impossible once the satellite was launched.
“Now we know that our key infrastructure is at risk on the ground as it is in space, from both physical and cyber-threats,” Melroy stated.
The Real Threats to Space Today
Attacks against space-based infrastructure including satellites are not theoretical either.
Melroy noted that the simplest type of attack is a Denial of Service (DoS) which is essentially a signal jamming activity. She added that it already happens now, sometimes inadvertently, that a space-based signal is blocked. There is also a more limited risk that a data transmission could be intercepted and manipulated by an attacker.
What isn’t particularly likely though is some kind of attack where an adversary attempts to direct one satellite to hit another. That said, Melory said that there could be a risk from misconfiguring a control system that would trigger a satellite to overheat or shut down.
How the ISS Secures its Network
During her presentation, Melroy outlined the many different steps that NASA and its international partners have taken to help secure the IT systems on-board ISS.
The entire network by which NASA controllers at Mission Control communicate with ISS is a private network, operated by NASA. Melroy emphasized that the control does not go over the open internet at any point.
There is also a very rigorous verification system for any commands and data communications that are sent from the ground to ISS. Melroy noted that the primary idea behind the verification is not necessarily about malicious hacking, but rather about limiting the risk of a ground controller sending a bad command to space.
“There’s a very rigorous certification process required for controllers in the International Space Station Mission Control Center (MCC) to allow them to send commands to the space station,” she explained. “In addition there are screening protocols both before a message ever leaves MCC going up to the ISS and once it’s on board ISS, to check and make sure that the command will not inadvertently do some damage to the station.”
Using Twitter in Space
ISS also makes use of a highly distributed architecture such that different sets of systems and networks are isolated from one another.
For station operations, Melroy said that astronauts make use of technology known as Portable Computer Systems (PCS) which are essentially remote terminals to send commands to the station’s primary computing units.
There is also a local area network on the station with support computers used for limited internet access including email and social media like Twitter. While the local ISS network has internet access, it is not directly connected to the public internet.
Melroy explained that there is a proxy computer inside the firewall at the Johnson Space Center, in Houston, Texas, that is connected with ISS. As such, the space station support computers talk to the proxy computer, which then goes out onto the public internet.
“Now of course, just like any computer, it’s still subject potentially to malware,” Melory said. “However, the most important thing is that the station support computers in no way shape or form are networked to the actual commanding of the station, they’re completely separate systems and they don’t talk to each other.”
Areas of Concern for Spaceflight Security
While ISS has multiple layers of security, Melroy commented that there are still some areas of concern for spaceflight and space cybersecurity.
For satellites, she noted that the uplink and downlink to most satellites is encrypted, though the data on-board the satellite often is not. Additionally, she expressed concern about ground-based control systems for satellites. Melroy explained that satellite ground systems have the same cybersecurity risks as any enterprise IT system.
“The most serious problem I think we have in space is complacency, many people in space think that their systems are not vulnerable to cyber-attacks,” Melroy said. “We are going to have to figure out how to insert cybersecurity and an awareness of that into the values and the culture of aerospace, all the way from the beginning in design and through to operations.”