Control: 4.11 Ensure a notification is configured for network security group changes

Description

It is recommended to setup an Event Rule and Notification that gets triggered when network security groups are created, updated or deleted. Event Rules are compartment scoped and will detect events in child compartments, it is recommended to create the Event rule at the root compartment level.

Network Security Groups control traffic flowing between Virtual Network Cards attached to Compute instances. Monitoring and alerting on changes to Network Security Groups will help in identifying changes these security controls.

Remediation

From Console

1. Go to the Events Service page.
2. Select the compartment that should host the rule.
3. Click Create Rule.
4. Provide a Display Name and Description.
5. Create a Rule Condition by selecting Networking in the Service Name Drop-down and selecting Network Security Group – Change Compartment, Network Security Group – Create, Network Security Group - Delete and Network Security Group – Update.
6. In the Actions section select Notifications as Action Type.
7. Select the Compartment that hosts the Topic to be used.
8. Select the Topic to be used.
9. Optionally add Tags to the Rule.
10. Click Create Rule.

From CLI

1. Find the topic-id of the Event Rule which should be used for sending Notifications by using the topic name and Compartment OCID.

oci ons topic list --compartment-id=<compartment OCID> --all --query "data [?name=='<topic_name>']".{"name:name,topic_id:\"topic-id\""} --output table

2. Create a JSON file to be used when creating the Event Rule. Replace topic id, display name, description and compartment OCID.

{
  "actions":
  {
    "actions": [
    {
      "actionType": "ONS",
      "isEnabled": true,
      "topicId": "<topic id>"
    }]
  },
  "condition":
  {
    "eventType":
      ["com.oraclecloud.virtualnetwork.changenetworksecuritygroupcompartment",
      "com.oraclecloud.virtualnetwork.createnetworksecuritygroup",
      "com.oraclecloud.virtualnetwork.deletenetworksecuritygroup",
      "com.oraclecloud.virtualnetwork.updatenetworksecuritygroup"],
    "data":{}
  },
  "displayName": "<display name>",
  "description": "<description>",
  "isEnabled": true,
  "compartmentId": "compartment OCID"
}

3. Create the actual event rule.

oci events rule create --from-json file://event_rule.json

4. Note in the JSON returned that it lists the parameters specified in the JSON file provided and that there is an OCID provided for the Event Rule.