Unrestricted Admin Port Access

ID: unrestricted-admin-ports

Severity: high

Author: princechaddha

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

Description

Checks for unrestricted ingress on TCP ports 22 (SSH) and 3389 (RDP) in Amazon VPC NACLs, exposing remote server administration to potentially malicious traffic.

YAML Source

id: unrestricted-admin-ports
info:
  name: Unrestricted Admin Port Access
  author: princechaddha
  severity: high
  description: |
    Checks for unrestricted ingress on TCP ports 22 (SSH) and 3389 (RDP) in Amazon VPC NACLs, exposing remote server administration to potentially malicious traffic.
  impact: |
    Allows unrestricted remote access, increasing the risk of unauthorized access and potential compromise.
  remediation: |
    Restrict access to ports 22 and 3389 to trusted IPs or IP ranges to adhere to the Principle of Least Privilege (POLP).
  reference:
    - https://docs.aws.amazon.com/vpc/latest/userguide/vpc-network-acls.html
  metadata:
    max-request: 2
  tags: cloud,devops,aws,amazon,vpc,aws-cloud-config
variables:
  region: "us-east-1"

flow: |
  code(1)
  for(let NACLIDs of iterate(template.nacls)){
    set("naclid", NACLIDs)
    code(2)
  }

self-contained: true
code:
  - engine:
      - sh
      - bash
    source: |
      aws ec2 describe-network-acls --region $region --query 'NetworkAcls[*].NetworkAclId' --output json

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

  - engine:
      - sh
      - bash
    source: |
         aws ec2 describe-network-acls --region $region --network-acl-ids $naclid --query 'NetworkAcls[*].Entries[?(RuleAction==`allow`) && (Egress==`false`)] | []' --output json

    matchers-condition: and
    matchers:
      - type: word
        words:
          - "0.0.0.0/0"
          - "CidrBlock"
        condition: and

      - type: word
        words:
          - "22"
          - "3389"
        condition: or

    extractors:
      - type: dsl
        dsl:
          - '"Access to the VPC subnets associated with your NACL " + naclid + " is not restricted."'
# digest: 490a00463044022014f1d1f13b7858c0c82e35525357ead3e90d95fdb5cdba6b2c5da7d8812c93ae02200c7b6cf3b3c92d03d233728479101c3b98c16251834adbe4eed5f32f2c766c00:922c64590222798bb761d5b6d8e72950

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/unrestricted-admin-ports.yaml"

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