このエラーメッセージに関する原因と対処に関して説明します。
エラーメッセージ(英語)：
cp access denied
対処
関連リンク
aws s3 cp filename s3://bucket/path/to/filename に必要な IAM Policy ...
https://qiita.com/rch850/items/068a323e50b906384930
S3 の「HTTP 403: Access Denied」(アクセスが ... - AWS - Amazon.com
https://aws.amazon.com/jp/premiumsupport/knowledge-center/s3-troubleshoot-403/
AWS Developer Forums: S3バケットが「Access Denied」エラーで削除も操作もで ...
https://forums.aws.amazon.com/thread.jspa?threadID=271455
access denied on CopyObject ...
https://forums.aws.amazon.com/thread.jspa?threadID=263871
ListObjects: Access denied (using CLI) ...
https://forums.aws.amazon.com/thread.jspa?threadID=173124
新しく提供されたAWS CLI(Command Line ...
https://forums.aws.amazon.com/thread.jspa?threadID=137448
Why does S3 return 403 Access Denied ...
https://forums.aws.amazon.com/thread.jspa?threadID=56531
S3にPutObjectするときの権限で注意したいこと - ばーろぐわにる
https://www.noobs.tokyo/entry/2018/10/15/213237
aws cli - What is causing Access Denied when using the aws cli to ...
https://serverfault.com/questions/556077/what-is-causing-access-denied-when-using-the-aws-cli-to-dow・・・
permissions - Access Denied when syncing between s3 buckets ...
https://serverfault.com/questions/810890/access-denied-when-syncing-between-s3-buckets-on-different-・・・