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# GCP Kubernetes Engine Clusters not using Container-Optimized OS for Node image misconfiguration dete

## Rule Details

|                        |                                      |
| ---------------------- | ------------------------------------ |
| Cortex AppSec Rule ID  | APPSEC\_GCP\_22                      |
| Category - Subcategory | Kubernetes - Resource Management     |
| Provider               | GCP                                  |
| Severity               | LOW                                  |
| Framework              | Terraform, Terraform Plan            |
| Mapped CSPM/KSPM Rule  | 84aedafc-aec4-4e7d-a604-a0a0ea1fd3ca |

## Impact

GKE enables users to select the operating system image that runs on each node. You can also upgrade an existing cluster to use a different node image type. GKE supports several OS images using the main container runtime directly integrated with Kubernetes, including *cos\_containerd* and *ubuntu\_containerd*. We recommend you use *cos\_containerd* and *ubuntu\_containerd* to enhance node security. *Containerd* is an industry-standard container runtime component that regularly updates security fixes and patches, providing better support, security, and stability than other images.

## How to Fix

Add the *image\_type* argument into the *node\_config* bloc to your *google\_container\_cluster* or *google\_container\_node\_pool* resource:

***

## hcl node\_config { image\_type = "COS" }

It should force the cluster to recreate a node following the new configuration. For further information please follow this link: <https://www.terraform.io/docs/providers/google/r/container\\_cluster.html#image\\_type>


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