Which action should be prioritized when an organization identifies a new significant cybersecurity threat?

The most appropriate action to prioritize when an organization identifies a new significant cybersecurity threat is enhancing employee training on cyber hygiene. This is because employees often serve as the first line of defense against cyber threats, and they need to be equipped with the knowledge and skills to recognize, respond to, and mitigate potential risks. By improving awareness around safe online practices, proper data handling, and recognizing phishing attempts, the organization can significantly reduce the likelihood of human errors that lead to security breaches.

Proactively training employees ensures they understand the current threat landscape and how to navigate it safely. This not only enhances security posture but also fosters a culture of vigilance and responsibility throughout the organization. Furthermore, employee training can be an ongoing process, adapting to emerging threats as the cyber landscape evolves.

Addressing the other actions: while documenting the threat in the risk register is a necessary activity for tracking and managing risks, it does not directly combat or mitigate the threat in real time. Increasing security measures without prior analysis could lead to unnecessary spending or implementing ineffective solutions without understanding the specific contours of the threat or its potential impact. Finally, engaging law enforcement without informing management might create issues regarding communication and coordination within the organization, as management should be aware of significant threats to make informed decisions.