The answer is to enable S3 MFA Delete on the log bucket and add a bucket policy that denies s3:DeleteObject to all principals except the CloudTrail service. MFA Delete requires multi-factor authentication for any delete operation, directly preventing unauthorized deletion of CloudTrail logs even if credentials are compromised. The bucket policy further locks down deletion by ensuring only CloudTrail itself can remove objects, which is rarely needed. On the AWS Certified Security Specialty SCS-C02 exam, this question tests your understanding of defense-in-depth for log integrity, often appearing as a two-part answer where versioning alone is a trap—it allows delete markers without true protection. A common memory tip is to think “MFA + policy = double lock” for deletion prevention, while encryption (SSE-S3) and CloudWatch streaming only protect data at rest or visibility, not deletion.
SCS-C02 Security Logging and Monitoring Practice Question
This SCS-C02 practice question tests your understanding of security logging and monitoring. 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.
Which TWO actions should a security engineer take to ensure that CloudTrail logs are protected from unauthorized deletion? (Choose two.)
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Attach an S3 bucket policy that denies s3:DeleteObject to all principals except the CloudTrail service principal.
Option A is correct because enabling S3 MFA Delete requires MFA to delete objects. Option D is correct because a bucket policy denying s3:DeleteObject for all principals except the CloudTrail service ensures only CloudTrail can delete (which is rare). Option B is wrong because enabling SSE-S3 protects data at rest but not deletion. Option C is wrong because logging to CloudWatch does not prevent deletion. Option E is wrong because versioning alone does not prevent deletion (delete markers can be created).
Key principle: ACLs process entries top to bottom and stop at the first match. Entry order and interface direction matter as much as the permit or deny statement.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✓
Attach an S3 bucket policy that denies s3:DeleteObject to all principals except the CloudTrail service principal.
Why this is correct
This restricts deletion to only CloudTrail.
Related concept
Standard ACLs match source addresses.
✗
Enable S3 versioning on the log bucket.
Why it's wrong here
Versioning alone does not prevent deletion; delete markers can be added.
✗
Enable S3 default encryption with SSE-S3.
Why it's wrong here
Encryption does not prevent deletion.
✗
Configure CloudTrail to send logs to CloudWatch Logs.
Why it's wrong here
CloudWatch Logs does not prevent deletion of S3 objects.
✓
Enable S3 MFA Delete on the log bucket.
Why this is correct
MFA Delete requires additional authentication to delete objects.
Related concept
Standard ACLs match source addresses.
Common exam traps
Common exam trap: ACLs stop at the first match
ACLs are processed top to bottom. The first matching entry wins, and an implicit deny usually exists at the end.
Detailed technical explanation
How to think about this question
ACL questions test precision: source, destination, protocol, port and direction. A generally correct ACL can still fail if it is applied on the wrong interface or in the wrong direction.
KKey Concepts to Remember
Standard ACLs match source addresses.
Extended ACLs can match source, destination, protocol and ports.
The first matching ACL entry is used.
There is usually an implicit deny at the end.
TExam Day Tips
→Check inbound versus outbound direction.
→Read the ACL from top to bottom.
→Look for a broader permit or deny above the intended line.
Key takeaway
ACLs process entries top to bottom and stop at the first match. Entry order and interface direction matter as much as the permit or deny statement.
Real-world example
How this comes up in practice
A media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.
What to study next
Got this wrong? Here's your next step.
Review ACL processing order, placement rules (standard near destination, extended near source), and inbound vs outbound direction. Study wildcard masks and implicit deny. Then practise related SCS-C02 ACL questions on filtering logic and placement.
Security Logging and Monitoring — This question tests Security Logging and Monitoring — Standard ACLs match source addresses..
What is the correct answer to this question?
The correct answer is: Attach an S3 bucket policy that denies s3:DeleteObject to all principals except the CloudTrail service principal. — Option A is correct because enabling S3 MFA Delete requires MFA to delete objects. Option D is correct because a bucket policy denying s3:DeleteObject for all principals except the CloudTrail service ensures only CloudTrail can delete (which is rare). Option B is wrong because enabling SSE-S3 protects data at rest but not deletion. Option C is wrong because logging to CloudWatch does not prevent deletion. Option E is wrong because versioning alone does not prevent deletion (delete markers can be created).
What should I do if I get this SCS-C02 question wrong?
Review ACL processing order, placement rules (standard near destination, extended near source), and inbound vs outbound direction. Study wildcard masks and implicit deny. Then practise related SCS-C02 ACL questions on filtering logic and placement.
What is the key concept behind this question?
Standard ACLs match source addresses.
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 →
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.
This SCS-C02 practice question is part of Courseiva's free Amazon Web Services 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 SCS-C02 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.