In a cybersecurity incident response, which action is considered a priority during active investigation?

During an active investigation of a cybersecurity incident, quarantining affected endpoints is considered a priority. This action is critical because it helps to contain the incident and prevent further spread of the threat within the network. Quarantining affected systems ensures that any malicious activity is isolated, which mitigates the risk of data theft, damage, or further compromise.

Immediately isolating these endpoints allows incident response teams to analyze and understand the threat without risking additional systems. This containment strategy is essential for preserving evidence, which can be vital for forensic investigations and later remediation efforts. Effective incident response relies heavily on the ability to quickly identify and limit the impact of a security breach, making the quarantine action a fundamental part of that process.

In contrast, implementing new firewall rules, updating ACL rules, and regular updates to software may be beneficial in enhancing overall security posture, but these actions do not provide the immediate containment necessary during an active threat investigation. They might be more relevant in the remediation phase once the immediate threat has been addressed.