Outages or destruction of Critical Infrastructures (CIs) cause disruption of fundamental services for Society's well being and result in diverse consequences with economical and social implications. An analysis of all the occurrences that can cause such undesired events is necessary. This calls for an all- hazard approach capable of dealing with diverse events and conditions such as deterioration and failures, natural disasters, accidents and malevolent acts. In this paper, an All-HAZard ANalysis (A- HAZAN) framework is proposed. Starting from the identification of the task of each component in the infrastructure, we use a Table to organize the information on the susceptibility to attacks, and to single and cascading failures. We qualitatively assess the susceptibility to attacks as a function of size, level of demand, level of protection and social criticality. Then, we give a methodology to rank the components with respect to their susceptibility to attacks. The systematic process of analysis is here presented by way of its application to a case study of literature.