Attack graphs are models that offer significant capabilities to analyse security in network systems. An attack graph allows the representation of vulnerabilities, exploits and conditions for each attack in a single unifying model. This paper proposes a methodology to explore the graph using a genetic algorithm (GA). Each attack path is considered as an independent attack scenario from the sourc...

A transitive signature scheme allows a signer to publish a graph in an authenticated and cost-saving manner. The resulting authenticated graph is indeed the transitive closure of the graph constructed by edges which are explicitly signed by the signer. A property of the transitive signature scheme enables such scenario is called composability. Composability means that by knowing signatures on t...

Adversarial attacks on Graph Neural Networks (GNNs) reveal their security vulnerabilities, limiting adoption in safety-critical applications. However, existing attack strategies rely the knowledge of either GNN model being used or predictive task attacked. Is this necessary? For example, a graph may be for multiple downstream tasks unknown to practical attacker. It is thus important test vulner...