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Conceptual model · 1 min read

Browser messages need separate trust checks

Original defensive model combining OWASP messaging and authorization guidance with the linked historical cases. These are independent design checks, not a vendor patch diagram or an operational reproduction.

The conceptual model

An incoming browser message first passes origin, sender-context and format validation. A separate decision checks the operation and recipient. Failed checks reject the message without disclosure or state change. Approved content remains data and only the permitted action is performed.
An incoming browser message first passes origin, sender-context and format validation. A separate decision checks the operation and recipient. Failed checks reject the message without disclosure or state change. Approved content remains data and only the permitted action is performed.
Full-size SVG ↗Mermaid source ↓Graphviz source ↓

Cases and references behind the model

DisclosureFacebook SDK message authentication relied on insecure randomness ↗DisclosureMeta Pixel cross-window handling lost message and token authority ↗ReferenceHTML5 Security Cheat Sheet: Web Messaging ↗ReferenceAuthorization Cheat Sheet ↗

Sources and provenance

  1. cheatsheetseries.owasp.org Primary source
  2. cheatsheetseries.owasp.org Primary source
  3. ysamm.com Primary source
  4. ysamm.com Primary source

Record reviewed 2026-10-02. Snapshot 53796974ace8. Open the complete JSON contract.

GitHub snapshot 2026-10-04

53796974ace8 · JSON exports & schemas · CC BY 4.0 content / MIT software