OSS Bucket Public Accessible

ID: oos-bucket-public-access

Severity: high

Author: DhiyaneshDK

Tags: cloud,devops,aliyun,alibaba,aliyun-cloud-config,alibaba-oss

Description

Ensure that your Object Storage Service (OSS) buckets are not publicly accessible to the Internet in order to protect against unauthorized access. Allowing public, anonymous access through bucket ACLs and bucket policies gives everyone the ability to access bucket contents.

YAML Source

id: oos-bucket-public-access

info:
  name: OSS Bucket Public Accessible
  author: DhiyaneshDK
  severity: high
  description: |
    Ensure that your Object Storage Service (OSS) buckets are not publicly accessible to the Internet in order to protect against unauthorized access. Allowing public, anonymous access through bucket ACLs and bucket policies gives everyone the ability to access bucket contents.
  reference:
    - https://www.trendmicro.com/cloudoneconformity/knowledge-base/alibaba-cloud/AlibabaCloud-OSS/publicly-accessible-oss-bucket.html
    - https://www.alibabacloud.com/help/en/oss/user-guide/block-public-access
  metadata:
    max-request: 2
    verified: true
  tags: cloud,devops,aliyun,alibaba,aliyun-cloud-config,alibaba-oss

variables:
  region: "cn-hangzhou"

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

self-contained: true

code:
  - engine:
      - sh
      - bash

    source: |
      aliyun oss ls --region $region

    extractors:
      - type: regex
        name: bucketname
        internal: true
        regex:
          - 'oss://([a-zA-Z0-9-]+)'

  - engine:
      - sh
      - bash

    source: |
      aliyun oss stat $bucket --region $region

    matchers-condition: and
    matchers:
      - type: word
        words:
          - 'private'
        negative: true

      - type: word
        words:
          - 'public-read'
          - 'public-read-write'
        condition: or

    extractors:
      - type: dsl
        dsl:
          - 'bucket + " OSS Bucket is Public Accessible "'
# digest: 4b0a00483046022100ebe3f235d7b322069926037bb46627b158f4c3aaef6fce8f53d5b7796c00d1f6022100a423932d5a987382196d74de46a97ba1dcb4b25980a28181945ee69c70512e45:922c64590222798bb761d5b6d8e72950

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/alibaba/oss/oos-bucket-public-access.yaml"

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