easyMultiple Choice
CS0-003 Practice Question: A company's IDS generated an alert for a SQL…
A company's IDS generated an alert for a SQL injection attempt against a web server. The web application firewall (WAF) is already in place. What is the best action?
⚠ Common exam trap
CS0-004 often tests the misconception that the first response to an IDS alert is to block or update defenses — candidates must remember that verifying whether the attack succeeded (impact analysis) precedes containment or rule changes.
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
✓
Verify if the attack succeeded by checking server logs
When an IDS alerts on a SQL injection attempt against a web server that already has a WAF, the WAF may have blocked it — but you cannot assume that. The best next step is to verify whether the attack succeeded by inspecting web server, application, and database logs for evidence of successful injection (e.g., unexpected queries, error messages, data exfiltration). Confirming impact drives the correct response and avoids unnecessary or disruptive actions.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Update the WAF rules
Why it's wrong here
Updating WAF rules assumes the signature set is deficient, but the alert shows the attempt already occurred, so the immediate priority is containment and investigation of whether it succeeded. Rule tuning is the right action when repeated false positives or gaps in detection coverage are identified.
- ✗
Block the source IP at the firewall
Why it's wrong here
Blocking the source IP at the firewall is ineffective against SQL injection, which arrives over HTTP/HTTPS on ports the firewall must keep open, and the attacker's address is likely spoofed or rotating. IP blocking is correct for volumetric or brute-force attacks originating from a fixed, identifiable source.
- ✗
Shut down the web server
Why it's wrong here
Shutting down the web server halts the business service rather than blocking the malicious traffic; the WAF already filters SQL injection, so the correct action is to review and tune its rules or block the source. Shutdown suits confirmed active compromise requiring immediate containment, not a single blocked attempt.
- ✓
Verify if the attack succeeded by checking server logs
Why this is correct
An IDS only detects; the WAF may have blocked the attempt or it may have succeeded. Checking server and database logs confirms whether the injection actually executed, which determines whether this is a true incident requiring response or a blocked attempt to document.
Go deeper
Related to this question
Learn chapter
Zero-Day Vulnerability Response
Key term
Web Application Firewall
A Web Application Firewall (WAF) is a security tool that monitors, filters, and blocks HTTP traffic to and from a web application to protect it from common attacks.
Key term
Alert
An alert is a notification that something unusual or potentially harmful has happened in a computer system or network.
About these practice questions
This CS0-004 question is part of Courseiva's 701-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam 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.