Quick Answer
The correct answer is the DNS Security profile. This profile is specifically engineered to detect and block DNS tunneling, a technique where attackers exfiltrate data by encoding it within DNS queries and responses, bypassing traditional firewalls. It inspects DNS traffic for anomalies like abnormally high query rates, suspiciously long or random-looking domain names, and non-standard record types, which are hallmarks of tunneling activity. On the PCNSA exam, this question tests your understanding of which security profile provides specialized DNS-layer inspection, as opposed to general profiles like Antivirus or Vulnerability Protection, which lack this capability. A common trap is assuming a URL Filtering or WildFire profile can stop tunneling, but only the DNS Security profile has the deep packet inspection needed for this threat. Memory tip: think of DNS Security as the “tunnel buster”—if data is trying to sneak out through DNS queries, this profile is the only one that can spot the hidden tunnel.
This PCNSA practice question tests your understanding of securing traffic. 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 organization wants to prevent data exfiltration via DNS tunneling. Which security profile should be applied to the outbound DNS traffic?
DNS Security profile
DNS Security is designed to detect and block DNS tunneling.
Vulnerability Protection profile
Why wrong: Vulnerability Protection blocks exploits, not DNS tunneling.
URL Filtering profile
Why wrong: URL Filtering is for web traffic, not DNS.
Anti-Spyware profile
Why wrong: Anti-Spyware is for malware C2, not specifically DNS tunneling.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
DNS Security profile
DNS Security profile is specifically designed to detect and block DNS tunneling, which is a technique used to exfiltrate data by encoding it within DNS queries and responses. By inspecting DNS traffic for anomalies such as high query rates, unusual domain names, or non-standard record types, the DNS Security profile can identify and prevent data exfiltration attempts. Other security profiles do not have the specialized DNS-layer inspection capabilities required to counter this threat.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
DNS Security profile
Why this is correct
DNS Security is designed to detect and block DNS tunneling.
Related concept
Read the scenario before looking for a memorised answer.
Vulnerability Protection profile
Why it's wrong here
Vulnerability Protection blocks exploits, not DNS tunneling.
URL Filtering profile
Why it's wrong here
URL Filtering is for web traffic, not DNS.
Anti-Spyware profile
Why it's wrong here
Anti-Spyware is for malware C2, not specifically DNS tunneling.
Common exam traps
The trap here is that candidates often confuse DNS Security with Anti-Spyware, assuming that spyware signatures will catch tunneling, but DNS tunneling is a protocol-level evasion technique that requires dedicated DNS inspection, not just signature-based malware detection.
Detailed technical explanation
DNS tunneling works by encapsulating non-DNS data (e.g., files, commands) within DNS query and response fields, often using TXT or NULL record types, and exfiltrating it to an attacker-controlled authoritative DNS server. The DNS Security profile in Palo Alto Networks firewalls uses machine learning and signature-based detection to identify abnormal DNS patterns, such as high entropy in domain names (e.g., 'base64-encoded-data.example.com'), excessive NXDOMAIN responses, or unusually large DNS packets. In a real-world scenario, an attacker might use tools like dnscat2 or Iodine to establish a covert channel; the DNS Security profile can block this by enforcing DNS policy and alerting on suspicious traffic.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A practitioner preparing for the PCNSA 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
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Securing Traffic — study guide chapter
Learn the concepts, then practise the questions
Securing Traffic practice questions
Targeted practice on this topic area only
All PCNSA questions
524 questions across all exam domains
Palo Alto Networks Certified Network Security Administrator PCNSA study guide
Full concept coverage aligned to exam objectives
PCNSA practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise PCNSA questions linked to Managing Objects.
Practise PCNSA questions linked to Policy Evaluation and Management.
Practise PCNSA questions linked to Securing Traffic.
Practise PCNSA questions linked to Core Concepts.
Practise PCNSA questions linked to Palo Alto Networks Platforms and Architecture.
Practise PCNSA questions linked to Device Management and Services.
Practise PCNSA questions linked to App-ID and Content-ID.
Practise PCNSA questions linked to Decryption and Monitoring.
Practise PCNSA questions linked to PCNSA fundamentals.
Practise PCNSA questions linked to PCNSA scenario.
Practise PCNSA questions linked to PCNSA troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Securing Traffic — This question tests Securing Traffic — Read the scenario before looking for a memorised answer..
The correct answer is: DNS Security profile — DNS Security profile is specifically designed to detect and block DNS tunneling, which is a technique used to exfiltrate data by encoding it within DNS queries and responses. By inspecting DNS traffic for anomalies such as high query rates, unusual domain names, or non-standard record types, the DNS Security profile can identify and prevent data exfiltration attempts. Other security profiles do not have the specialized DNS-layer inspection capabilities required to counter this threat.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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 →
Last reviewed: Jun 11, 2026
This PCNSA practice question is part of Courseiva's free Palo Alto Networks 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 PCNSA 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.