> For the complete documentation index, see [llms.txt](https://docs.panther.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.panther.com/~/changes/Dd8nx2iqd1Pp2OzWJaWk/alerts/alert-runbooks/built-in-policies/aws-s3-bucket-not-publicly-readable.md).

# AWS S3 Bucket Not Publicly Readable

| Risk     | Remediation Effort |
| -------- | ------------------ |
| **High** | **Low**            |

This policy validates that no S3 buckets are publicly readable. Overly permissive S3 buckets are a major cause of data loss in AWS. Be extremely careful when making buckets publicly available.

**Remediation**

To remediate this, modify the access policy of the S3 bucket to remove `AllUsers` and `AuthenticatedUsers` from any grant that gives read permissions.

**Reference**

* AWS S3 Bucket [example policies](https://docs.aws.amazon.com/AmazonS3/latest/dev/example-bucket-policies.html)


---

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