Cybersecurity of air traffic management and aviation systems: a systems engineering approach to risk mitigation
Creators: name: Bogoda, Lanka
Publisher: name: RMIT University
Year: 2024
Subjects: classificationCode: 400103
subject: Aircraft performance and flight control systems
classificationCode: 401005
subject: Risk engineering

description: Autonomy in flight operations has reconceptualised the aerospace cybersecurity paradigm to a new era. Cybersecurity is about preventing or mitigating malicious acts undertaken to either compromise systems directly or access valuable information that could be subject to criminal misuse. The cybersecurity of Communication, Navigation, and surveillance / Air Traffic Management (CNS/ATM) systems aims to control the effects of such threats and enhance the safety of flying passengers. Besides, complicated risk management issues have impacted the cyber resilience of state-of-the-art CNS/ATM and avionics systems. The security of legacy aviation and airport infrastructure has been curtailed owing to their annexure to public networks, which constitute a significant risk to the aviation industry and the general public as a whole.

The industry and the governing bodies such as  International Civil Aviation Organization(ICAO) and Civil Air Navigation Services Organisation (CANSO) recognise that digital transformation is a definite requirement for the industry to evolve and provide efficient services. However, this effort introduced new constraints to aircraft manufacturers, airlines, air navigation service providers and air traffic service providers; cybersecurity.
 
Aviation cybersecurity issues have remained despite the enormous effort to remediate multiple openings to breaches. Numerous incidents have been reported with the intention of gaining financial advantages and causing malicious acts to take lives on some occasions. This scenario is far from a worst-case scenario where malevolent players take control of a securely connected aircraft or ATM system. The growth of the digital aviation landscape also paves the way for potential security vulnerabilities owing to information sharing and open telecommunication and network architecture.
  
To defend against possible breaches and enhance resilience in the security space, regional aviation authorities have reportedly updated their information system security frameworks on many fronts, including event management and new standards dedicated to systems. The aerospace system suppliers, manufacturers, and academia also strive to curb cyber threats.

The prevailing control mechanisms in place, with the aim of assuring Confidentiality, Integrity, and Availability (CIA) of information, have a multitude of deficiencies in deciding the extent of vulnerability of systems, the severity of impact and subsequently, overall risk rating. Weaknesses in some of the security controls which are intended to mitigate the impact of cyber-attacks also contribute to this issue. A risk-based system engineering solution is envisioned for managing today's cyber-physical systems, which may comprise interwound Systems of Systems (SoS). This research investigates threats to aviation assets and vulnerabilities of aviation systems and recommends a holistic approach to mitigate possible risks. The thesis also proposes a novel framework to manage risks by enhancing the consistency and accuracy of risk attributes of CNS/ATM systems, Avionics and Airport systems.
In order to meet the objectives specified, a significant effort was put into studying the usage of systems engineering products, processes, people and environment (3PE) in the context of aviation-related IT/OT and their interaction. As a part of this process, exploitable cyber security vulnerabilities were investigated in the key domains: Aircraft, CNS/ATM and Airport systems.

 Cybersecurity threat hunting was performed as part of intelligence collection. The information on the Dark Web has been an excellent source for attacking methods and exploits that are potentially successful in compromising systems. Threat hunting has been a labour-intensive assignment by an analyst – interpreting the context. A large portion of the thesis comprised intelligence collection and can be used as a body of knowledge by security professionals in the industry. Successfully exposing any of these vulnerabilities using penetration test techniques can be used as new threat signatures for IPS and IDS solutions to protect aerospace systems.

 In meeting one of the primary research objectives, an effective risk assessment technique is developed to improve how risks are appropriately identified and determine an effective method to prioritise risks. Mainly the approach is discussed, analysed and applied using test cases and described. This process involved security governance principles, testing and audit, risk classifications and attributes, and measuring and prioritising business risk. It also examined the external threat to aviation systems, how these threats impede operations, and the possible consequences of a cyber attack, and they are listed for future research.

The research also investigated various system security architecture frameworks that can systematically improve the identification of risks and mitigate them effectively. A further in-depth study has demonstrated why the standard (non-aviation related) security framework does not fully address specific threats against current and potential vulnerabilities in the aerospace industry and describes implications.
 
The identified deficiencies in the existing frameworks are described while proposing changes to minimise the impact of cyber incidents by reducing the uncertainty of cyber security risk attributes. For this purpose, a broad investigation of the literature was performed and ranked the severity of risk attributes based on their industry acceptance and minimising the impact by reducing uncertainty.

The research also presents the pragmatic industry-specific risk management framework for aviation systems that could be employed and enhance the security risk management process. The section describes the application of the framework and attributes of risk parameters and various methodologies that can be utilised to improve security attributes.