ANS-C01 Network Security, Compliance and Governance Practice Question

Exhibit

Refer to the exhibit.

```
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": "*",
      "Action": "s3:GetObject",
      "Resource": "arn:aws:s3:::my-bucket/*",
      "Condition": {
        "IpAddress": {
          "aws:SourceIp": "10.0.0.0/16"
        }
      }
    }
  ]
}
```

Refer to the exhibit. A company applies this bucket policy to an S3 bucket. Users in a different VPC with IP range 10.0.0.0/16 are able to access objects, but users in a different VPC with IP range 10.1.0.0/16 cannot. What is the most likely cause?

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

✓

The users are accessing the bucket through a NAT Gateway, which changes the source IP

The users in 10.1.0.0/16 are likely accessing the bucket through a NAT Gateway, which translates their private source IPs to the NAT's public IP. The bucket policy uses 'aws:SourceIp' with the condition '10.1.0.0/16', but after NAT, the source IP is no longer in that range, causing access to be denied. Option A is incorrect because the condition key 'aws:SourceIp' is appropriate; the problem is the IP after translation. Option C is incorrect because the resource ARN is specified correctly. Option D is incorrect because bucket policies can be written without a principal to apply to all principals; it's valid.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
The bucket policy uses the wrong condition key
Why it's wrong here
'aws:SourceIp' is correct for IP-based conditions.
✓
The users are accessing the bucket through a NAT Gateway, which changes the source IP
Why this is correct
NAT changes private IP to public IP, which does not match the condition.
✗
The bucket policy specifies the wrong resource ARN
Why it's wrong here
The resource ARN is correct for the bucket.
✗
The bucket policy does not specify a principal
Why it's wrong here
Principal '*' allows all, so that is not the issue.

Visual reference

Quick reference

AWS S3 Storage Class Comparison

Storage Class	Min Duration	Retrieval	Use Case
S3 Standard	None	Immediate	Frequently accessed data
S3 Standard-IA	30 days	Immediate	Infrequent access, rapid retrieval
S3 One Zone-IA	30 days	Immediate	Non-critical infrequent data
S3 Intelligent-Tiering	None	Immediate–hours	Unknown or changing access patterns
S3 Glacier Instant	90 days	Milliseconds	Archive with instant retrieval
S3 Glacier Flexible	90 days	Minutes–hours	Archive, flexible retrieval
S3 Glacier Deep Archive	180 days	Hours	Long-term compliance archive

Go deeper

ANS-C01 Network Security, Compliance and Governance Practice Question

Exhibit

Why each option matters

Option-by-option breakdown

AWS S3 Storage Class Comparison

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