This paper examines the emergent security risk that information warfare poses to critical infrastructure systems, particularly as governments are increasingly concerned with protecting these assets against attack or disruption. Initially it outlines critical infrastructure systems and the notion of information warfare. It then discusses the potential implications and examining the concerns and vulnerabilities such cyber attacks would pose, utilising exemplar online attack occurrences. It then examines the current Australian situation before suggesting some considerations to mitigate the potential risk that information warfare poses to critical infrastructure systems, and by association: government, industry and the wider community.