In incident response, what is the first step in dealing with malicious software detected in a system?

The first step in dealing with malicious software detected in a system is to isolate the affected system. This action is crucial because it prevents the malware from spreading to other devices or systems on the network. By isolating the affected system, you ensure that the threat is contained and that no further damage can occur while the incident response team assesses the situation.

Isolation gives the incident response team the opportunity to analyze the malware without the risk of it impacting other parts of the organization. This step also allows for a more thorough investigation to understand the nature and scope of the infection, as well as to formulate a response strategy without outside interference or immediate risk of escalation.

Eradicating the malware, educating users, or ignoring the detection would put the entire organization at risk, either by potentially escalating the incident or failing to address the threat adequately. Hence, isolating the affected system is the logical and essential initial response in handling malicious software incidents effectively.