Analysis and Design of Stealthy Cyber Attacks on UAS
Cyber security has emerged as one of the most important issues in unmanned aerial systems for which the functionality heavily relies on onboard automation and intervehicle communications.
In this paper, potential cyber threats and vulnerabilities in the unmanned aerial system’s state estimator to stealthy cyber attacks are identified, which can avoid being detected by the monitoring system. Specifically, this paper investigates the worst stealthy cyber attack that can maximize the state estimation error of the unmanned aerial system’s state estimator while not being detected.
First, the condition that the system is vulnerable to the stealthy cyber attacks is derived, and then;
an analytical method is provided to identify the worst stealthy cyber attack.
Cyber attack detection mechanism for UAS
The proposed cyber attack analysis methods are demonstrated with illustrative examples of an onboard unmanned aerial system navigation system and an unmanned aerial system tracking application.
Onboard UAS Navigation System
Onboard UAS navigation system architecture
Trajectory estimates under three different case 3 attack (both sensors and actuators are compromised)
The estimated UAS trajectories under the three different case 3 attacks significantly deviate from the actual UAS trajectory without being detected
The UAS can be hijacked to any place that the attacker wants.
Attack performance with Monte Carlo simulations (1000 runs)
Each attack can easily cause the large estimation error
The residuals under attack have no significant change in their statistical properties, which implies the attacks are undetectable via the residual tests.
UAS Tracking from a Ground Station
Communications between UAS entities and a ground station
Attack performance with Monte Carlo simulations (1000 times)
The optimal cyber attacks can easily cause large estimation errors without being detected.
Demonstration of Stealthy cyber attack
Software In the Loop (SITL) simulator: construct and demonstrate realistic attacks to assess their impact and risk
Hardware In the Loop (HITL) Simulator: demonstrate concrete attacks to confirm discovered vulnerabilities on real hardware
Normal operation without attack: aircraft takes off, follows the waypoints, then begins to land at the final waypoint (on runway)
Stealthy attack case
Attacker inserts a position bias into the GPS information of the aircraft
Attack monitoring system cannot detect the cyber-attack
Related Publication
C. Kwon, W. Liu and I. Hwang, “Analysis and Design of Stealthy Cyber Attacks on Unmanned Aerial Systems”, AIAA Journal of Aerospace Information Systems, Vol.11(8), pp. 525-539, August 2014