Final answer:
The investment firm should follow security incident handling models to handle the worm attack. These models provide a systematic approach to detecting, analyzing, and mitigating security incidents.
Step-by-step explanation:
This scenario is about a small, family-owned investment firm that is facing a worm attack. The worm spreads through removable media and open Windows shares, infecting hosts and installing a DDoS agent. Antivirus signatures become available several hours after the worm starts spreading, leading to widespread infections in the organization.
To handle this security incident, the investment firm should follow security incident handling models. These models provide a systematic approach to detecting, analyzing, and mitigating security incidents. Some common models include the NIST Incident Response Life Cycle, SANS Incident Handler's Handbook, and ISO/IEC 27035 Incident Management.
By following these models, the investment firm can effectively respond to the worm attack, identify the infected hosts, isolate and remediate them, and implement preventive measures to avoid future attacks.