> 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/public-exposure/appsec-aws-231.md).

# AWS NACL allows ingress from 0.0.0.0/0 to port 3389 misconfiguration detected in code

## Rule Details

|                        |                                   |
| ---------------------- | --------------------------------- |
| Cortex AppSec Rule ID  | APPSEC\_AWS\_231                  |
| Category - Subcategory | Public Exposure - Sensitive Ports |
| Provider               | AWS                               |
| Severity               | LOW                               |
| Framework              | Terraform                         |

## Impact

Network Access Control List (NACL) is stateless and provides filtering of ingress/egress network traffic to AWS resources. We recommend that NACLs do not allow unrestricted ingress access to port 3389. Removing unfettered connectivity to remote console services, such as RDP, reduces a server's exposure to risk.

## How to Fix

## \[source,go]

resource "aws\_network\_acl\_rule" "example" { network\_acl\_id = aws\_network\_acl.example.id rule\_number = 200 egress = false protocol = "tcp" rule\_action = "allow"

* cidr\_block = "0.0.0.0/0"
* cidr\_block = "10.0.0.0/32" from\_port = 3389 to\_port = 3389 }

***


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