Managed NAT Gateway Usage

ID: nat-gateway-use

Severity: medium

Author: princechaddha

Tags: cloud,devops,aws,amazon,vpc,aws-cloud-config

Description

Ensure the use of Amazon Managed NAT Gateway for better availability and bandwidth in VPC networks instead of self-managed NAT instances.

YAML Source

id: nat-gateway-use
info:
  name: Managed NAT Gateway Usage
  author: princechaddha
  severity: medium
  description: |
    Ensure the use of Amazon Managed NAT Gateway for better availability and bandwidth in VPC networks instead of self-managed NAT instances.
  impact: |
    Using self-managed NAT instances can lead to single points of failure and potential bandwidth bottlenecks.
  remediation: |
    Replace NAT instances with Amazon Managed NAT Gateway to ensure high availability and scalability in your VPC network.
  reference:
    - https://docs.aws.amazon.com/vpc/latest/userguide/vpc-nat-gateway.html
  metadata:
    max-request: 2
  tags: cloud,devops,aws,amazon,vpc,aws-cloud-config
variables:
  region: "us-east-1"

flow: |
  code(1)
  for(let VPCIds of iterate(template.vpcid)){
    set("vpc", VPCIds)
    code(2)
  }

self-contained: true
code:
  - engine:
      - sh
      - bash
    source: |
      aws ec2 describe-vpcs --region $region --query 'Vpcs[*].VpcId' --output json

    extractors:
      - type: json
        name: vpcid
        internal: true
        json:
          - '.[]'

  - engine:
      - sh
      - bash
    source: |
         aws ec2 describe-nat-gateways --region $region --filter "Name=vpc-id,Values=$vpc" "Name=state,Values=available" --query 'NatGateways'

    matchers:
      - type: word
        words:
          - "[]"

    extractors:
      - type: dsl
        dsl:
          - 'vpc + " VPC is not using Managed NAT Gateways"'
# digest: 4a0a00473045022033924463ca3a49819ef3a786daa7e1529d24ad878c48b4282bf78a07c0dfd8d9022100caad07d20ef7d1885a9a3c3b06ab5472afb05d075bda5dde5371c879a9633f46:922c64590222798bb761d5b6d8e72950

Guide to check the vulnerabilities

This template is used to detect vulnerabilities in web applications. It can be used with the Nuclei tool to scan for specific patterns or behaviors.

$ nuclei -u "URL" -t "cloud/aws/vpc/nat-gateway-usage.yaml"

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