> For the complete documentation index, see [llms.txt](https://cortex-docs.paloaltonetworks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cortex-docs.paloaltonetworks.com/appsec-rules/iac-security/storage/appsec-aws-298.md).

# The DMS S3 does not use a Customer Managed Key (CMK) misconfiguration detected in code

## Rule Details

|                        |                           |
| ---------------------- | ------------------------- |
| Cortex AppSec Rule ID  | APPSEC\_AWS\_298          |
| Category - Subcategory | Storage - Encryption      |
| Provider               | AWS                       |
| Severity               | HIGH                      |
| Framework              | Terraform, Terraform Plan |

## Impact

This rule is checking to ensure that the AWS Database Migration Service (DMS) S3 is utilizing a Customer Managed Key (CMK) for encryption. If this rule is not adhered to, it could potentially create a security risk as AWS managed keys may not provide the same level of control and access restrictions that a CMK would. This could leave sensitive data exposed or vulnerable to unauthorized access or breaches.

## How to Fix

*Resource:* aws\_dms\_s3\_endpoint

* *Arguments:* kms\_key\_arn

To fix this issue, you need to set the "kms\_key\_arn" attribute in your DMS S3 configuration block.

## The above Terraform code is secure because by adding kms\_key\_arn parameter with the value of the ARN of the Customer Managed Key, you ensure that a Customer Managed Key is used with DMS S3. This allows you to have more granular control over data encryption and decryption. \[source,go]

resource "aws\_dms\_s3\_endpoint" "test\_dms\_endpoint\_s3" {

* kms\_key\_arn = "arn:aws:kms:us-west-2:111122223333:key/abcd1234-a123-456a-a12b-a123b4cd56ef" ... }

***


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