Quick Answer
The correct rule placement is to put the allow rule before the deny all rule. This is because a stateful firewall with a default-deny policy processes rules sequentially from top to bottom, so the explicit permit for HTTP traffic (TCP port 80) must be evaluated first to match and allow the desired packets before the catch-all deny rule drops everything else. On the CISSP exam, this concept tests your understanding of firewall rule ordering and the principle of least privilege, often appearing in questions about access control lists or network security architecture. A common trap is assuming a default-deny policy automatically allows known traffic, but the deny all rule will block it if placed first, making the allow rule unreachable. Remember the memory tip: “First allow, then deny—or your traffic will say goodbye.”
This CISSP practice question tests your understanding of communication and network security. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. 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.
A security administrator is configuring a stateful firewall to allow HTTP traffic from the internet to a web server. The firewall uses a default-deny policy. What is the correct rule placement?
Place the allow rule after the deny all rule
Why wrong: Would block the traffic before the allow rule is evaluated.
Use a stateless firewall instead
Why wrong: Does not address rule placement issue.
Use an implicit deny rule
Why wrong: Implicit deny is always at the end, but allow rule must come first.
Place the allow rule before the deny all rule
Ensures the traffic is permitted before the default deny.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
Place the allow rule before the deny all rule
In a stateful firewall with a default-deny policy, rules are processed in sequential order from top to bottom. Placing the allow rule before the deny all rule ensures that HTTP traffic (TCP port 80) is explicitly permitted before the catch-all deny rule drops all unmatched packets. If the deny all rule were placed first, all traffic would be dropped, including the intended HTTP traffic, making the allow rule unreachable.
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.
Place the allow rule after the deny all rule
Why it's wrong here
Would block the traffic before the allow rule is evaluated.
Use a stateless firewall instead
Why it's wrong here
Does not address rule placement issue.
Use an implicit deny rule
Why it's wrong here
Implicit deny is always at the end, but allow rule must come first.
Place the allow rule before the deny all rule
Why this is correct
Ensures the traffic is permitted before the default deny.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
ISC2 often tests the misconception that a default-deny policy automatically allows traffic if a permit rule exists anywhere in the ACL, but in reality, rule order determines which rule is applied first, and a deny all placed before the permit will block all traffic.
Detailed technical explanation
Stateful firewalls maintain a connection table that tracks the state of TCP sessions (e.g., SYN, SYN-ACK, ACK). When an HTTP request from the internet reaches the web server, the firewall creates a state entry; return traffic from the server is automatically permitted if it matches an existing session, without needing explicit allow rules for ephemeral ports. In real-world deployments, rule order is critical because the first matching rule is applied; a common best practice is to place specific allow rules (e.g., permit tcp any host 10.1.1.1 eq 80) before the global deny all rule to avoid unintended blocking.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A security analyst at a medium-sized enterprise encounters this scenario during an investigation or architecture review. The correct answer reflects best practice for the specific threat or control described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Security exam questions test whether you can match controls to threats in context — not just recall definitions.
What to study next
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Communication and Network Security — study guide chapter
Learn the concepts, then practise the questions
Communication and Network Security practice questions
Targeted practice on this topic area only
All CISSP questions
529 questions across all exam domains
Certified Information Systems Security Professional CISSP study guide
Full concept coverage aligned to exam objectives
CISSP 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 CISSP questions linked to Software Development Security.
Practise CISSP questions linked to Security Assessment and Testing.
Practise CISSP questions linked to Identity and Access Management.
Practise CISSP questions linked to Security and Risk Management.
Practise CISSP questions linked to Security Architecture and Engineering.
Practise CISSP questions linked to Communication and Network Security.
Practise CISSP questions linked to Asset Security.
Practise CISSP questions linked to Security Operations.
Practise CISSP questions linked to CISSP fundamentals.
Practise CISSP questions linked to CISSP scenario.
Practise CISSP questions linked to CISSP troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Communication and Network Security — This question tests Communication and Network Security — Read the scenario before looking for a memorised answer..
The correct answer is: Place the allow rule before the deny all rule — In a stateful firewall with a default-deny policy, rules are processed in sequential order from top to bottom. Placing the allow rule before the deny all rule ensures that HTTP traffic (TCP port 80) is explicitly permitted before the catch-all deny rule drops all unmatched packets. If the deny all rule were placed first, all traffic would be dropped, including the intended HTTP traffic, making the allow rule unreachable.
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 →
Same concept, more angles
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. Refer to the exhibit. The firewall rules above are applied to the outside interface. A penetration tester from the internet attempts to establish a connection to 192.168.1.10 on TCP port 8080. What will happen?
mediumWhy D: Option D is correct because firewall rules operate on an implicit-deny model: if no rule explicitly permits traffic, it is denied by default. Since the exhibit shows no rule allowing TCP port 8080 from the internet to 192.168.1.10, the connection is dropped. The destination is reachable (192.168.1.10 is a valid internal IP), but the lack of an explicit permit for port 8080 causes the denial.
Last reviewed: Jun 30, 2026
This CISSP practice question is part of Courseiva's free ISC2 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 CISSP 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.