The answer is that a system is infected with malware that is beaconing to a command and control server. This is the most likely issue because the IDS alert specifically flags a malware beacon pattern, and the firewall log confirms periodic outbound connections to a single external IP address, which is the classic signature of command and control traffic. On the Certified Information Security Manager CISM exam, this scenario tests your ability to correlate disparate log sources—here, an IDS alert and a firewall log—to identify a live infection rather than a false positive or a benign application. A common trap is to mistake regular software updates or DNS queries for beaconing, but beaconing is distinguished by its consistent, low-and-slow timing and lack of user-initiated triggers. Remember the memory tip: “Beacons blink on a schedule, not on demand”—if the outbound traffic is periodic and not tied to user activity, suspect C2 communication.
CISM Incident Management Practice Question
This CISM practice question tests your understanding of incident management. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. 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.
Exhibit
Refer to the exhibit.
Exhibit:
Firewall Log:
Date Time Source IP Destination IP Port Protocol Action
2023-10-05 10:00:00 10.0.0.15 203.0.113.5 443 TCP ALLOW
2023-10-05 10:01:00 10.0.0.15 203.0.113.5 443 TCP ALLOW
2023-10-05 10:02:00 10.0.0.15 203.0.113.5 443 TCP ALLOW
... (repeated every minute)
2023-10-05 12:00:00 10.0.0.15 203.0.113.5 443 TCP ALLOW
IDS Alert:
Signature: ET TROJAN Win32/Malicious Beacon
Source IP: 10.0.0.15
Destination IP: 203.0.113.5
Time: 2023-10-05 10:00:00
Severity: High
Based on the exhibit, what is the MOST likely issue?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "most likely"
Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
A system is infected with malware that is beaconing to a command and control server.
The IDS alert indicates a malware beacon, and the firewall log shows periodic outbound connections to an external IP, which is typical of command and control traffic.
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.
✓
A system is infected with malware that is beaconing to a command and control server.
Why this is correct
The combination of IDS alert and periodic connections is indicative of C2 activity.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
✗
A user is streaming video from a legitimate site.
Why it's wrong here
Streaming would not trigger a malware beacon alert.
✗
A software update is being downloaded from an external site.
Why it's wrong here
Software updates are not typically periodic every minute and would not trigger such an alert.
✗
A network scan is being performed from the internal IP.
Why it's wrong here
A scan would show multiple destinations, not a single IP.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Trap categories for this question
Command / output trap
A scan would show multiple destinations, not a single IP.
Detailed technical explanation
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
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.
Use explanations to understand the rule behind the answer.
TExam Day Tips
→Underline the problem statement mentally.
→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 practitioner preparing for the CISM exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
What to study next
Got this wrong? Here's your next step.
Identify which CISM exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
Incident Management — This question tests Incident Management — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: A system is infected with malware that is beaconing to a command and control server. — The IDS alert indicates a malware beacon, and the firewall log shows periodic outbound connections to an external IP, which is typical of command and control traffic.
What should I do if I get this CISM question wrong?
Identify which CISM exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
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 CISM practice question is part of Courseiva's free ISACA 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 CISM 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.