What is an appropriate local internal action in response to detected malicious code?

Quarantine or cleaning the affected files is the most appropriate local internal action in response to detected malicious code because it directly addresses the immediate threat to the system. When malicious code is identified, the priority is to contain it and prevent its spread or any further damage. Quarantine involves isolating the infected files to ensure that they cannot execute or spread to other parts of the network, which helps maintain system integrity and security.

Cleaning the affected files means removing the malicious code to restore the system to its normal state, allowing it to function without the threat of the malware impacting operations. This action is crucial for mitigating risk quickly and ensuring that operational disruptions are minimized.

While reporting the incident, notifying upper management, or restarting infected systems are also important steps in a comprehensive incident response plan, they do not address the immediate risk posed by the malicious code in the same direct and effective manner as quarantining or cleaning the files. Thus, taking immediate local action to contain and remediate the threat is vital for protecting the organization’s IT environment.