IoT Policy Allows Wildcard Resource

• Query id: be5b230d-4371-4a28-a441-85dc760e2aa3
• Query name: IoT Policy Allows Wildcard Resource
• Platform: CloudFormation
• Severity: Medium
• Category: Access Control
• URL: Github

Description

IoT Policy should not allow Resource to be set as *
Documentation

Code samples

Code samples with security vulnerabilities

Postitive test num. 1 - yaml file

AWSTemplateFormatVersion: 2010-09-09
Description: A sample template
Resources:
    IoTPolicy:
      Type: AWS::IoT::Policy
      Properties:
        PolicyDocument:
          Version: '2012-10-17'
          Statement:
          - Effect: Allow
            Action:
            - iot:Connect
            Resource: "*"
          - Effect: Deny
            Action:
            - sqs:*
            NotResource: my-hardcoded-arn
        PolicyName: PolicyName

Postitive test num. 2 - json file

{
  "Description": "A sample template",
  "Resources": {
    "IoTPolicy": {
      "Type": "AWS::IoT::Policy",
      "Properties": {
        "PolicyDocument": {
          "Version": "2012-10-17",
          "Statement": [
            {
              "Action": [
                "iot:Connect"
              ],
              "Resource": "*",
              "Effect": "Allow"
            },
            {
              "Effect": "Deny",
              "Action": [
                "sqs:*"
              ],
              "NotResource": "my-hardcoded-arn"
            }
          ]
        },
        "PolicyName": "PolicyName"
      }
    }
  },
  "AWSTemplateFormatVersion": "2010-09-09T00:00:00Z"
}

Code samples without security vulnerabilities

Negative test num. 1 - yaml file

AWSTemplateFormatVersion: 2010-09-09
Description: A sample template
Resources:
    IoTPolicy:
      Type: AWS::IoT::Policy
      Properties:
        PolicyDocument:
          Version: '2012-10-17'
          Statement:
          - Effect: Allow
            Action:
            - iot:Connect
            Resource:
            - arn:aws:iot:us-east-1:123456789012:client/client1
        PolicyName: PolicyName

Negative test num. 2 - json file

{
  "AWSTemplateFormatVersion": "2010-09-09T00:00:00Z",
  "Description": "A sample template",
  "Resources": {
    "IoTPolicy": {
      "Type": "AWS::IoT::Policy",
      "Properties": {
        "PolicyDocument": {
          "Version": "2012-10-17",
          "Statement": [
            {
              "Effect": "Allow",
              "Action": [
                "iot:Connect"
              ],
              "Resource": [
                "arn:aws:iot:us-east-1:123456789012:client/client1"
              ]
            }
          ]
        },
        "PolicyName": "PolicyName"
      }
    }
  }
}