A system and method for protecting a computer system connected to a communication network from a potential vulnerability. The system and method protects a computer system that is about to undergo or has just undergone a change in state that may result in placing the computer system at risk to viruses, and the like, over a communication network. The system and method first detect an imminent or recent change in state. A security component and a fixing component react to the detection of the change in state. The security component may raise the security level to block incoming network information, other than information from a secure or known location, or information requested by the computer system. The fixing component implements a fixing routine, such as installing missing updates or patches, and on successfully completing the fixing routine, the security level is relaxed or lowered.