This vulnerability (CVE-2026-87543) involves a missing authorization check in the core component of Google Chrome versions before 153.0.8010.36. An attacker who has already compromised the renderer process can exploit this flaw to bypass site isolation protections by delivering a specially crafted HTML page. Site isolation is a security feature designed to separate different websites into different processes to prevent data leaks and cross-site attacks. The vulnerability is categorized under CWE-862 (Missing Authorization). No known exploits in the wild have been reported, and no patch or remediation details are provided in the source data.

The impact is limited to bypassing site isolation protections after the attacker has compromised the renderer process. This could potentially allow access to data or processes that should be isolated between sites. However, the overall severity is considered low by the Chromium security team, indicating limited risk or difficulty of exploitation.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no patch or official fix information is provided, users and administrators should monitor official Google Chrome security advisories for updates. Until a fix is available, limiting exposure to malicious content that could compromise the renderer process is advisable.