Quick Answer
The answer is DNS logs. This is the most useful additional data source because command and control traffic frequently relies on domain generation algorithms or connections to known malicious domains, and DNS logs directly reveal the domain names being resolved before the outbound connections on port 443 occur. By correlating the firewall logs with DNS queries, an analyst can spot suspicious lookups that precede the encrypted C2 handshake, exposing the infrastructure behind the traffic. On the Systems Security Certified Practitioner SSCP exam, this tests your ability to prioritize evidence that links network behavior to threat actor tactics, often appearing in scenario-based questions where you must choose between NetFlow, system logs, or DNS logs—a common trap is picking NetFlow because it shows IPs, but DNS logs provide the domain-level context that confirms C2 activity. Memory tip: think “DNS reveals the destination name, not just the number.”
This SSCP practice question tests your understanding of incident response and recovery. Examine the command output carefully: the correct answer depends on what the output actually shows, not on general recall alone. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A security analyst reviews a firewall log showing an internal IP attempting outbound connections to multiple external IPs on port 443. The analyst suspects command and control. Which additional data source would be MOST useful for confirmation?
NetFlow data
Why wrong: NetFlow shows traffic flow but not DNS queries; less direct evidence.
System event logs
Why wrong: Event logs show process creation but not network connections to external IPs.
DNS logs
DNS logs can show domain resolutions, often used by C2 to obfuscate IPs.
Antivirus logs
Why wrong: Antivirus may not detect C2 traffic if malware is unknown.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
DNS logs
DNS logs are the most useful additional data source because C2 traffic often uses domain generation algorithms (DGAs) or connects to known malicious domains. By correlating the outbound connections on port 443 with DNS queries, the analyst can identify suspicious domain lookups that precede the connections, revealing the C2 infrastructure. Unlike NetFlow or system logs, DNS logs directly show the domain names being resolved, which is a key indicator of C2 activity.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
NetFlow data
Why it's wrong here
NetFlow shows traffic flow but not DNS queries; less direct evidence.
System event logs
Why it's wrong here
Event logs show process creation but not network connections to external IPs.
DNS logs
Antivirus logs
Why it's wrong here
Antivirus may not detect C2 traffic if malware is unknown.
Common exam traps
The trap here is that candidates often choose NetFlow data (Option A) because it shows traffic flows, but they overlook that DNS logs directly reveal the domain names being resolved, which is critical for identifying C2 domains that may not appear in NetFlow's IP-only view.
Trap categories for this question
Command / output trap
NetFlow shows traffic flow but not DNS queries; less direct evidence.
Detailed technical explanation
C2 traffic often uses HTTPS on port 443 to blend with legitimate web traffic, but DNS logs can reveal beaconing patterns such as periodic queries to algorithmically generated domains (e.g., using a DGA like in the Conficker or LockBit variants). A real-world scenario involves analyzing DNS logs for NXDOMAIN responses or high query volumes to rare TLDs, which are strong indicators of C2 activity even when the traffic itself is encrypted. Tools like Zeek or Windows DNS Server logs can capture these queries, and correlating them with firewall logs provides a more complete picture.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A developer is choosing between AES-256 (symmetric) and RSA-2048 (asymmetric) for encrypting a large file that will be sent to a partner. Symmetric encryption is fast but requires key exchange; asymmetric is slower but solves the key distribution problem. A hybrid approach — encrypt the file with AES, encrypt the AES key with RSA — is standard. Questions like this test whether you understand when each approach applies.
What to study next
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Incident Response and Recovery — study guide chapter
Learn the concepts, then practise the questions
Incident Response and Recovery practice questions
Targeted practice on this topic area only
All SSCP questions
504 questions across all exam domains
Systems Security Certified Practitioner SSCP study guide
Full concept coverage aligned to exam objectives
SSCP practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise SSCP questions linked to Risk Identification, Monitoring and Analysis.
Practise SSCP questions linked to Network and Communications Security.
Practise SSCP questions linked to Systems and Application Security.
Practise SSCP questions linked to Security Operations and Administration.
Practise SSCP questions linked to Incident Response and Recovery.
Practise SSCP questions linked to Access Controls.
Practise SSCP questions linked to Cryptography.
Practise SSCP questions linked to SSCP fundamentals.
Practise SSCP questions linked to SSCP scenario.
Practise SSCP questions linked to SSCP troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Incident Response and Recovery — This question tests Incident Response and Recovery — Read the scenario before looking for a memorised answer..
The correct answer is: DNS logs — DNS logs are the most useful additional data source because C2 traffic often uses domain generation algorithms (DGAs) or connects to known malicious domains. By correlating the outbound connections on port 443 with DNS queries, the analyst can identify suspicious domain lookups that precede the connections, revealing the C2 infrastructure. Unlike NetFlow or system logs, DNS logs directly show the domain names being resolved, which is a key indicator of C2 activity.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Last reviewed: Jun 25, 2026
This SSCP practice question is part of Courseiva's free ISC2 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 SSCP exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.