Executive brief
Google Chrome contains a missing authorization vulnerability in its Core component that could allow an attacker who has compromised the browser's renderer process to bypass site isolation protections. Site isolation is a critical security boundary designed to prevent malicious websites from accessing data in other browser tabs and websites. Exploitation requires that the renderer process be already compromised, which typically follows another vulnerability, making this a medium-severity chain vulnerability rather than a direct attack vector.
Technical details
This vulnerability is a missing authorization check in Chrome's Core component that allows an attacker with control of the renderer process to bypass site isolation protections via a crafted HTML page. Site isolation is Chrome's sandbox mechanism that isolates each website in its own process to prevent cross-site data theft; the missing authorization allows an already-compromised renderer to break this isolation boundary. The attack requires prior compromise of the renderer process (typically through another vulnerability) and network delivery of a malicious HTML page. An attacker can leverage this to access data from other sites that the victim is browsing. Chrome 153.0.8010.36 and later contain the fix for this issue.
Affected products
- Google Chrome prior to 153.0.8010.36
Timeline
- 2026-09-08: patched: Fixed in Chrome 153.0.8010.36