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# AWS Elastic File System (EFS) with encryption for data at rest is disabled misconfiguration detected

## Rule Details

|                        |                                                       |
| ---------------------- | ----------------------------------------------------- |
| Cortex AppSec Rule ID  | APPSEC\_AWS\_42                                       |
| Category - Subcategory | Storage - Encryption                                  |
| Provider               | AWS                                                   |
| Severity               | LOW                                                   |
| Framework              | CloudFormation, Serverless, Terraform, Terraform Plan |
| Mapped CSPM/KSPM Rule  | 5eb50d57-7e94-4204-a4e7-3471b3f7e82e                  |

## Impact

Amazon Elastic File System (Amazon EFS) is a simple, scalable file storage solution for AWS services and on-premises resources. Amazon EFS is built to elastically scale on-demand. It grows and shrinks automatically as files are added and removed. It is essential to encrypt your Amazon EFS to protect data and metadata against unauthorized access. Encrypting your Amazon EFS also fulfils compliance requirements for data-at-rest encryption when file systems are used in production systems.

## How to Fix

*Resource:* AWS::EFS::FileSystem

* *Arguments:* Encrypted - (Optional) If true, the disk will be encrypted. If you are using AWS KMS you can optionally provides a KMS customer master key. \[source,go]

***

Resources: FileSystemResource: Type: 'AWS::EFS::FileSystem' Properties: ...

* Encrypted: true

***


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