  In an increasingly interconnected world, where information is the lifeblood
of modern society, regular cyber-attacks sabotage the confidentiality,
integrity, and availability of digital systems and information. Additionally,
cyber-attacks differ depending on the objective and evolve rapidly to disguise
defensive systems. However, a typical cyber-attack demonstrates a series of
stages from attack initiation to final resolution, called an attack life cycle.
These diverse characteristics and the relentless evolution of cyber attacks
have led cyber defense to adopt modern approaches like Machine Learning to
bolster defensive measures and break the attack life cycle. Among the adopted
ML approaches, Graph Neural Networks have emerged as a promising approach for
enhancing the effectiveness of defensive measures due to their ability to
process and learn from heterogeneous cyber threat data. In this paper, we look
into the application of GNNs in aiding to break each stage of one of the most
renowned attack life cycles, the Lockheed Martin Cyber Kill Chain. We address
each phase of CKC and discuss how GNNs contribute to preparing and preventing
an attack from a defensive standpoint. Furthermore, We also discuss open
research areas and further improvement scopes.
