CS0-003 Security Operations Practice Question
A threat intelligence report indicates that a known APT group is using 'regsvr32.exe' to execute malicious code. Which detection rule type would be most effective in identifying this technique across multiple endpoints?
⚠ Common exam trap
CS0-004 often tests the confusion between network-based detection (Snort/Suricata) and host-based detection (Sigma/YARA), and between file-signature matching (YARA) and behavioral process matching (Sigma).
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
✓
Sigma rule
Sigma is a generic, open signature format for log-based detection rules that can be converted to multiple SIEM query languages (Splunk, Elastic, Sentinel, etc.). Because the question asks for a rule type effective across multiple endpoints and the technique involves process execution (regsvr32.exe), a Sigma rule targeting process creation events is the most portable and effective choice. It can be deployed across heterogeneous endpoint detection platforms.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Snort rule
Why it's wrong here
Snort is an open-source network intrusion detection and prevention system (IDS/IPS). Its rules analyze packet payloads and network protocol headers in transit, making them incapable of parsing local endpoint event logs or monitoring process execution events like regsvr32.exe spawning on a host.
- ✗
YARA rule
Why it's wrong here
YARA is a tool primarily designed for malware classification and file-based pattern matching on disk or in memory. While highly effective for identifying static indicators within binaries or active process memory dumps, it is not designed to parse structured event logs to detect live process creation arguments.
- ✗
Suricata rule
Why it's wrong here
Suricata is a high-performance network threat detection engine that inspects live network traffic, PCAP files, and protocol transactions. Because it operates entirely at the network layer, it cannot inspect local endpoint operating system logs to identify specific command-line arguments used during a process execution.
- ✓
Sigma rule
Why this is correct
Sigma is an open, standardized signature format designed specifically for describing log events in a SIEM-neutral manner. It allows security analysts to write rules targeting process creation logs (such as Windows Event ID 1) to detect malicious command-line executions, such as regsvr32.exe loading remote scripts, which can then be converted into target SIEM queries like Splunk or ELK.
Go deeper
Related to this question
Learn chapter
Endpoint Detection and Response
Key term
SIEM
SIEM (Security Information and Event Management) is a system that collects and analyzes log data from across an IT environment to detect and respond to security threats in real time.
Key term
Threat
A threat is any potential danger that could harm a computer system, network, or data, whether from a malicious hacker, a natural disaster, or an accidental mistake.
About these practice questions
Courseiva writes every CS0-004 question from scratch — 701 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. 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 CompTIA exam blueprint
This CS0-004 practice question is part of Courseiva's free CompTIA 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 CS0-004 exam.