Question 40
During a post-incident review at a research campus, the original problem was: A contractor's User-ID group is used on a permit rule but the firewall has no current user-to-IP mapping for VPN clients. Which preventive practice most directly addresses its cause?
Explanation
Correct Answer
Monitor User-ID mapping freshness and authentication integrations for remote access. This control reduces recurrence of the documented mechanism: Identity-based policy cannot match as intended when user mapping is missing or stale. It creates a repeatable check around the needed response: Restore the supported identity mapping source and verify group membership before widening the rule.
Incorrect Answers
Maintain application dependency maps and negative access tests for segmentation. That safeguard addresses another potential failure: A datacenter denies all east-west traffic based on broad zones, unintentionally disrupting a necessary monitored backup application. It is not the most targeted recurring control for the described cause: Identity-based policy cannot match as intended when user mapping is missing or stale.
Route centrally managed rule changes through their authoritative configuration scope. That safeguard addresses another potential failure: An analyst edits a local firewall Security policy while the same rule is centrally managed and overwritten by the next cloud push. It is not the most targeted recurring control for the described cause: Identity-based policy cannot match as intended when user mapping is missing or stale.
Use observed ingress and egress zones in policy match tests before committing. That safeguard addresses another potential failure: A branch security rule with source zone untrust matches no internal outgoing requests because the actual ingress is the inside zone. It is not the most targeted recurring control for the described cause: Identity-based policy cannot match as intended when user mapping is missing or stale.