GHSA-G5QX-H5F3-MP2F TinaCMS: Cross-origin postMessage handlers and rich-text URL-sanitization bypass enable stored XSS and session takeover

TinaCMS registers window message listeners — the useTina overlay handler, the OAuth authentication popup handler, and the admin↔preview iframe GraphQL reducer — that act on event.data without verifying event.origin or event.source, and post messages using non-specific target origins. A page the...

CVE-2026-2345 Insufficient Origin Validation in Proctorio Chrome Extension postMessage Handlers

Proctorio Chrome Extension is a browser extension used for online proctoring. The extension contains multiple window.addEventListener'message', ... handlers that do not properly validate the origin of incoming messages. Specifically, an internal messaging bridge processes messages based solely on...