ISC2 Systems Security Certified Practitioner (SSCP) Practice Question

Implementing new countermeasures means adding or enhancing security controls so the same type of incident is less likely to recur. Deploying internal segmentation firewalls and tightening access-control lists directly change the technical environment to block the lateral movement technique the attackers exploited, addressing the root cause discovered during analysis. Updating reports, running tabletop exercises, or revising escalation criteria are important post-incident tasks, but they concern documentation, training, or process refinement-not the actual deployment of preventive or detective safeguards. Therefore, rolling out segmentation firewalls and updated ACLs is the action that aligns with implementing new countermeasures.