The correct next step is to correlate the Snort alerts with authentication logs to confirm unsuccessful SSH login attempts. While the 'ET SCAN Potential SSH Scan' alert from Snort indicates repeated connection attempts to TCP port 22, it does not by itself prove malicious intent or actual breach attempts—it could be a misconfigured service or a legitimate scanner. By cross-referencing with authentication logs such as /var/log/auth.log on Linux or Event ID 4625 on Windows, the analyst can verify failed login attempts, which is the definitive evidence of an SSH brute-force attack. This action tests your understanding of the Cisco CyberOps Associate 200-201 exam objective on network intrusion analysis, specifically the principle of alert validation before escalation. A common trap is acting on the Snort alert alone without confirming the authentication failure pattern, which wastes resources on false positives. Remember the memory tip: "Snort spots the scan, but auth logs confirm the plan"—always validate an alert with a secondary log source to distinguish noise from a real threat.
200-201 Network Intrusion Analysis Practice Question
This 200-201 practice question tests your understanding of network intrusion analysis. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. 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.
An analyst is reviewing Snort alerts and notices repeated 'ET SCAN Potential SSH Scan' alerts from the same source IP. Which action should the analyst take next?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Correlate with authentication logs to confirm unsuccessful attempts.
Option A is correct because Snort alerts for 'ET SCAN Potential SSH Scan' indicate a pattern of connection attempts to the SSH port (TCP/22), but the alert alone does not confirm whether the attempts were successful or malicious. Correlating with authentication logs (e.g., /var/log/auth.log or Windows Event ID 4625) allows the analyst to verify failed login attempts, which is the definitive evidence of an actual SSH brute-force attack. This step aligns with the network intrusion analysis methodology of validating alerts before taking action.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✓
Correlate with authentication logs to confirm unsuccessful attempts.
Why this is correct
This provides evidence of actual brute force attempts, enabling informed decision-making.
Related concept
Read the scenario before looking for a memorised answer.
✗
Run a vulnerability scan on the destination.
Why it's wrong here
Vulnerability scanning is reactive and not the immediate next step for a potential scan.
✗
Ignore because it is a false positive.
Why it's wrong here
Alerts should be investigated; ignoring may miss a real threat.
✗
Immediately block the IP on the firewall.
Why it's wrong here
Blocking without verification could disrupt legitimate traffic and is not a standard first step.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Cisco often tests the principle that alerts must be validated with additional data sources (like logs) before taking action, trapping candidates who jump to blocking or ignoring based on the alert alone.
Detailed technical explanation
How to think about this question
Under the hood, the 'ET SCAN Potential SSH Scan' rule in Snort typically triggers on a threshold of SYN packets to TCP port 22 within a defined time window (e.g., more than 10 connections in 60 seconds). Authentication logs provide granular details such as usernames attempted, timestamps, and success/failure status (e.g., SSH auth failure messages with 'Failed password for invalid user'). In a real-world scenario, an analyst might use tools like 'grep' or SIEM correlation to match the source IP from the Snort alert against auth log entries, confirming whether the scan resulted in any successful logins—a critical step before escalating to blocking.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A small business has 20 workstations on the 192.168.1.0/24 network and one public IP from its ISP. The router uses PAT (NAT overload) so all 20 devices share one public address using different source ports. NAT questions test whether you understand the four address terms and which direction each translation applies.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Network Intrusion Analysis — This question tests Network Intrusion Analysis — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Correlate with authentication logs to confirm unsuccessful attempts. — Option A is correct because Snort alerts for 'ET SCAN Potential SSH Scan' indicate a pattern of connection attempts to the SSH port (TCP/22), but the alert alone does not confirm whether the attempts were successful or malicious. Correlating with authentication logs (e.g., /var/log/auth.log or Windows Event ID 4625) allows the analyst to verify failed login attempts, which is the definitive evidence of an actual SSH brute-force attack. This step aligns with the network intrusion analysis methodology of validating alerts before taking action.
What should I do if I get this 200-201 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
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 →
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.
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.
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.