CVE-2026-2300 — Cross-Site Scripting (XSS)

title: CVE-2026-2300 - BJ Lazy Load Stored XSS via filter_images
id: scw-2026-05-12-ai-1
status: experimental
level: high
description: |
  Detects attempts to exploit CVE-2026-2300 by sending a crafted payload to the BJ Lazy Load plugin's settings update endpoint. The payload targets the 'bj_lazy_load_images_quality' parameter, attempting to inject JavaScript within the 'class' attribute, which is then processed by the vulnerable `filter_images` function. This rule specifically looks for the admin-ajax.php endpoint, the relevant action, and the presence of script tags within the parameters, indicating a potential Stored XSS attack.
author: SCW Feed Engine (AI-generated)
date: 2026-05-12
references:
  - https://shimiscyberworld.com/posts/nvd-CVE-2026-2300/
tags:
  - attack.initial_access
  - attack.t1189
logsource:
    category: webserver
detection:
  selection:
      cs-uri|contains:
          - '/wp-admin/admin-ajax.php'
      cs-uri-query|contains:
          - 'action=bj_lazy_load_save_settings'
      cs-uri-query|contains:
          - 'bj_lazy_load_options[bj_lazy_load_images_options][bj_lazy_load_images_quality]'
      cs-uri-query|contains:
          - '<script>'
      condition: selection
falsepositives:
  - Legitimate administrative activity

Source: Shimi's Cyber World · License & reuse