Security Incident Response (SIR) Practice Test

Isolating affected systems immediately is the most effective action in mitigating damage during a security incident because it helps to prevent the spread of the incident, whether it's a malware infection, unauthorized access, or data breach. By cutting off the affected systems from the network, organizations can contain the threat and prevent it from reaching unaffected systems. This containment is critical in minimizing data loss, protecting sensitive information, and reducing the overall impact on the organization.

In contrast, implementing a new security policy might improve future incident readiness but will not address the immediate threat at hand, thus failing to mitigate current damage. Analyzing daily traffic patterns can provide insights and help in post-incident evaluations, but it doesn’t offer real-time mitigation during an active incident. Notifying all users of the incident can be important for awareness, but it doesn't provide a direct means to contain or address the damage happening in real time. Therefore, immediate isolation stands out as the most effective proactive measure during a security incident.