Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
A SOC analyst reviews DNS telemetry and sees a workstation resolving hundreds of algorithmically generated domains at fixed intervals, with most responses returning NXDOMAIN. What evidence should the analyst prioritize to validate command-and-control beaconing? In the evidence source phase, Which evidence source best supports or refutes the detection?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Distractor review
Search only for successful HTTP 200 responses
DGA activity may fail resolution frequently, so HTTP status codes alone miss the behaviour.
B
Distractor review
Delete the host from the SIEM asset inventory
Removing context makes investigation harder and does not contain the threat.
C
Distractor review
Block all DNS traffic from the subnet
Immediate blanket blocking may disrupt operations and does not validate the source process.
D
Best answer
Correlate DNS query logs with endpoint process and network connection telemetry
The pattern is suspicious, but process and connection context shows whether a host process is repeatedly attempting outbound C2 communication.
Common exam trap
Common exam trap: usable hosts are not the same as total addresses
Subnetting questions often tempt you into counting all addresses. In normal IPv4 subnets, the network and broadcast addresses are not usable host addresses.
Technical deep dive
How to think about this question
Subnetting questions test whether you can identify the network, broadcast address, usable range, mask and correct subnet. Slow down enough to calculate the block size correctly.
KKey Concepts to Remember
- CIDR notation defines the prefix length.
- Block size helps identify subnet boundaries.
- Network and broadcast addresses are not usable hosts in normal IPv4 subnets.
- The required host count determines the smallest suitable subnet.
TExam Day Tips
- Write the block size before choosing the subnet.
- Check whether the question asks for hosts, subnets or a specific address range.
- Do not confuse /24, /25, /26 and /27 host counts.
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More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A responder is acquiring evidence from a potentially compromised server. Which actions support forensic integrity? (Choose two.)
Question 2
A SOC wants to reduce alert fatigue without missing confirmed malicious activity. Which actions are appropriate? (Choose two.)
Question 3
A user reports approving an unexpected OAuth consent prompt for an app named 'Invoice Reader'. The app now has mailbox read permissions. What should the incident responder do first? During detection and analysis, which decision is most defensible?
Question 4
A business owner accepts delayed remediation for a production system. What must the report include? If the primary audience is business service owner, which content choice is most appropriate?
Question 5
A business owner accepts delayed remediation for a production system. What must the report include? If the primary audience is legal/privacy stakeholder, which content choice is most appropriate?
Question 6
A host alert shows certutil.exe downloading a file from an external URL, followed by execution from a user-writable directory. What should the analyst focus on? In the containment trade-off phase, Which response balances containment with evidence preservation?
FAQ
Questions learners often ask
What does this CS0-003 question test?
CIDR notation defines the prefix length.
What is the correct answer to this question?
The correct answer is: Correlate DNS query logs with endpoint process and network connection telemetry — The pattern is suspicious, but process and connection context shows whether a host process is repeatedly attempting outbound C2 communication. This keeps the analysis focused on evidence source rather than broad, low-value actions.
What should I do if I get this CS0-003 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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