S3 Bucket with Public READ_ACP Access

ID: s3-public-read-acp

Severity: critical

Author: princechaddha

Tags: cloud,devops,aws,amazon,s3,aws-cloud-config

Description

Verifies that Amazon S3 buckets do not permit public ‘READ_ACP’ (LIST) access to anonymous users, protecting against unauthorized data exposure

YAML Source

id: s3-public-read-acp

info:
  name: S3 Bucket with Public READ_ACP Access
  author: princechaddha
  severity: critical
  description: |
    Verifies that Amazon S3 buckets do not permit public 'READ_ACP' (LIST) access to anonymous users, protecting against unauthorized data exposure
  reference:
    - https://docs.aws.amazon.com/cli/latest/reference/s3api/get-bucket-acl.html
  metadata:
    max-request: 2
  tags: cloud,devops,aws,amazon,s3,aws-cloud-config

flow: |
  code(1)
  for(let bucketName of iterate(template.buckets)){
    set("bucket", bucketName)
    code(2)
  }

self-contained: true
code:
  - engine:
      - sh
      - bash
    source: |
      aws s3api list-buckets --query 'Buckets[*].Name'

    extractors:
      - type: json # type of the extractor
        internal: true
        name: buckets
        json:
          - '.[]'

  - engine:
      - sh
      - bash
    source: |
        aws s3api get-bucket-acl --bucket $bucket --query 'Grants[?(Grantee.URI==`http://acs.amazonaws.com/groups/global/AllUsers`)]'

    matchers:
      - type: word
        words:
          - '"Permission": "READ_ACP"'

    extractors:
      - type: dsl
        dsl:
          - '"The S3 bucket " + bucket +" have public READ_ACP access"'
# digest: 4a0a00473045022018893dcd711c223bd1710b044ac2ca975c026f4355112bd79f87dfe5b64d6974022100c180ed08579d6a9f946cc76bb08f9b7eba75d318a174178f44093b074c6b2da8:922c64590222798bb761d5b6d8e72950

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/s3/s3-public-read-acp.yaml"

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