1. Login to the AWS Management Console.
2. Navigate to the EC2 service.
3. Select the EC2 instance(s) for which you want to restrict RDP access.
4. Click on the “Security Groups” tab in the bottom pane.
5. Select the security group(s) associated with the instance(s).
6. Click on the “Inbound Rules” tab.
7. Locate the rule that allows RDP access from any IP address (0.0.0.0/0).
8. Click on the “Edit” button next to the rule.
9. Change the source IP address to a specific IP address or range of IP addresses that are allowed to access RDP.
10. Click on the “Save” button to apply the changes.
11. Repeat these steps for all instances that have unrestricted RDP access.

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1. Open the AWS CLI on your local machine.
2. Run the below command to list all the security groups in your AWS account.

aws ec2 describe-security-groups

3. Identify the security group that allows unrestricted RDP access.
4. Run the below command to revoke the inbound rule that allows unrestricted RDP access.

aws ec2 revoke-security-group-ingress --group-id <security-group-id> --protocol tcp --port 3389 --cidr 0.0.0.0/0

5. Verify that the inbound rule has been revoked by running the below command.

aws ec2 describe-security-groups --group-ids <security-group-id>

6. Repeat steps 3 to 5 for all the security groups that allow unrestricted RDP access.

1. Import the necessary AWS SDK libraries in your Python script. You can use the Boto3 library to interact with AWS services.

import boto3

2. Initialize the EC2 client using the Boto3 library.

ec2 = boto3.client('ec2')

3. Use the describe_security_groups method to get a list of all security groups in your AWS account.

response = ec2.describe_security_groups()
security_groups = response['SecurityGroups']

4. Loop through the security groups and check if any of them have an inbound rule allowing unrestricted RDP access (port 3389).

for sg in security_groups:
    for rule in sg['IpPermissions']:
        if rule['IpProtocol'] == 'tcp' and rule['FromPort'] == 3389 and rule['ToPort'] == 3389 and rule['IpRanges'] == [{'CidrIp': '0.0.0.0/0'}]:
            # Remove the rule that allows unrestricted RDP access
            ec2.revoke_security_group_ingress(
                GroupId=sg['GroupId'],
                IpPermissions=[rule]
            )

5. Save the Python script and run it to remove the rule that allows unrestricted RDP access in all security groups in your AWS account.

resource "aws_security_group" "rdp_restricted" {
  name        = "RDP_RESTRICTED_SG_NAME"        # replace with your SG name
  description = "Security group without unrestricted RDP"
  vpc_id      = "VPC_ID"                        # replace with your VPC ID

  # Example: allow RDP only from a trusted admin IP range (optional)
  # Remove this block entirely if you do not want RDP at all.
  ingress {
    description = "Restricted RDP access"
    from_port   = 3389
    to_port     = 3389
    protocol    = "tcp"
    cidr_blocks = ["TRUSTED_ADMIN_IP_CIDR"]     # e.g. "203.0.113.10/32"
    # ipv6_cidr_blocks = ["TRUSTED_ADMIN_IPV6_CIDR"]  # e.g. "2001:db8::/64"
  }

  # Other, non-RDP rules can remain as needed
  # Do NOT include any of the following:
  # - cidr_blocks      = ["0.0.0.0/0"] with from_port/to_port including 3389
  # - ipv6_cidr_blocks = ["::/0"]      with from_port/to_port including 3389

  egress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    cidr_blocks = ["0.0.0.0/0"]
  }

  tags = {
    Name = "RDP_RESTRICTED_SG_TAG_NAME"         # replace with your SG tag name
  }
}

• Any existing ingress rule with protocol = "tcp", from_port/to_port including 3389 and cidr_blocks = ["0.0.0.0/0"] and/or ipv6_cidr_blocks = ["::/0"] is shown as being removed.
• (Optionally) a new, more restrictive ingress rule for port 3389 from specific IP ranges is shown as being added.