A method of identifying a software vulnerability on a computer system is disclosed in which the computer system has software stored thereon and is connected to a management system over a computer network. The method comprises the steps of: applying an interrogation program to the software, the interrogation program being capable of exploiting a known software vulnerability if it is present in the software to which the interrogation program is applied; in the event that the software vulnerability is exploited by the interrogation program, operating the interrogation program to generate a set of management information from which can be derived the identification of the computer system; and sending the management information to the management system.