200-201 Security Monitoring Practice Question
An analyst is tuning a Cisco Firepower intrusion policy. A rule fires repeatedly with the message 'MALWARE-CNC Outbound connection to known malicious domain' against a marketing workstation. Packet capture shows the workstation resolving and connecting to a domain that the threat intelligence feed lists, but the endpoint shows no malicious process, no persistence, and the user states they clicked a link in a phishing email an hour earlier. Which action best reflects sound incident handling at this stage?
⚠ Common exam trap
The trap here is equating a clean endpoint scan with a clean host, when network evidence of an actual malicious connection can reflect fileless execution that disk-based tools do not detect.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Treat the alert as a probable compromise: isolate the workstation, capture volatile data, and correlate the connection timing with the phishing email and any subsequent downloads.
Network evidence of a live connection to a threat-intelligence-listed domain, occurring shortly after a user clicked a phishing link, justifies treating the workstation as potentially compromised. Endpoint scans often miss fileless or in-memory activity, so a clean disk does not clear the host. The proportionate response is containment with evidence preservation, followed by correlation across email, DNS, proxy, and endpoint telemetry to establish scope and determine whether credentials or data were affected.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Suppress the rule permanently for the marketing subnet so analysts are not distracted by future alerts.
Why it's wrong here
Permanent suppression for an entire subnet removes visibility into a category of activity that just proved relevant. The alert matched live traffic to an indicator, and the phishing context makes it more credible, not less. Tuning should be based on confirmed false positives with evidence, and none is presented here; this action would hide a potential compromise rather than investigate it.
- ✗
Close the ticket as a false positive because the endpoint security agent reported no malicious process on disk.
Why it's wrong here
Absence of an on-disk indicator does not clear the host. Fileless techniques, in-memory loaders, and living-off-the-land binaries frequently leave no persistent artifact for an endpoint scanner to find. The network evidence of an actual connection to a threat-intelligence-listed domain, combined with recent phishing exposure, outweighs a negative disk scan and justifies deeper investigation rather than closure.
- ✓
Treat the alert as a probable compromise: isolate the workstation, capture volatile data, and correlate the connection timing with the phishing email and any subsequent downloads.
Why this is correct
An outbound connection to a known malicious domain from a user who just clicked a phishing link is a strong compromise signal regardless of current endpoint findings. Early malware often leaves little on disk. Isolating preserves evidence, memory capture may reveal injected code or in-memory payloads, and correlating timing with the email establishes the intrusion chain before lateral movement or credential theft occurs.
- ✗
Block the domain at the DNS layer only and continue monitoring, since blocking prevents any further harm from the connection.
Why it's wrong here
DNS blocking may stop future lookups but does nothing about a session already established or a payload already delivered. If the workstation connected, code may already be resident or credentials may already have been harvested. Blocking is a useful containment layer, yet treating it as sufficient resolution skips host triage, evidence preservation, and scope determination that this phishing-linked event clearly requires.
Visual reference
Go deeper
Related to this question
About these practice questions
One of 968 original 200-201 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Cisco exam blueprint
This 200-201 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 200-201 exam.