Executive brief
Google Chrome's storage system has a missing authorization flaw that could allow an attacker who has already compromised the browser's renderer process to bypass Chrome's site isolation security feature using a specially crafted PDF file. Site isolation is Chrome's foundational security mechanism that prevents malicious websites from stealing data from other sites; bypassing it could enable cross-site data theft or manipulation.
Technical details
This vulnerability is a missing authorization check in Chrome's Storage component that allows an already-compromised renderer process to circumvent site isolation protections. The attack vector requires the renderer process to be compromised first (a prerequisite condition), after which an attacker can exploit the missing authorization check by providing a malicious PDF file to bypass the site isolation boundary. The Chromium security team rated this as Medium severity. The vulnerability was fixed in Chrome version 153.0.8010.52 and later versions.
Affected products
- Google Chrome prior to 153.0.8010.52
Timeline
- 2026-09-17: disclosed
- 2026-09-17: patched: Fixed in Chrome 153.0.8010.52/.53