One S3 object returns 403 while others in the same prefix download correctly

0 reputation · 16 Dec 2024, 23:42 UTC

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A fictional application reads most objects under an allowed prefix. A newer object returns AccessDenied. The newer object uses a different customer-managed KMS key. The bucket policy appears unchanged. Which evidence would distinguish S3 access from encryption-key access?

Environment

Editorial worked example. See the question for the scenario and assumptions.

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One S3 object returns 403 while others in the same prefix download correctly

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