CVE-2026-45243 — The Content Script Window.PostMessage Bridge That Vulnerability

title: CVE-2026-45243 - Unauthorized Automation Artifact Access via Spoofed Window.PostMessage
id: scw-2026-05-18-ai-1
status: experimental
level: high
description: |
  Detects attempts to access automation artifacts (list, read, create, overwrite, delete) via a web request, which could indicate exploitation of CVE-2026-45243. This rule specifically targets the URI and query parameters associated with unauthorized operations on automation artifacts through the vulnerable window.postMessage bridge.
author: SCW Feed Engine (AI-generated)
date: 2026-05-18
references:
  - https://shimiscyberworld.com/posts/nvd-CVE-2026-45243/
tags:
  - attack.initial_access
  - attack.t1190
logsource:
    category: webserver
detection:
  selection:
      cs-uri|contains:
          - '/automation/artifacts'
      cs-uri-query|contains:
          - 'action=list'
          - 'action=read'
          - 'action=create'
          - 'action=overwrite'
          - 'action=delete'
      condition: selection
falsepositives:
  - Legitimate administrative activity

Source: Shimi's Cyber World · License & reuse