CVE-2026-87553: Improper input validation in Google Chrome

This vulnerability in Google Chrome's SiteIsolation component is due to improper input validation. An attacker who has already compromised the renderer process could leverage this flaw to execute arbitrary code outside the sandbox environment by delivering a specially crafted HTML page. The issue affects versions prior to 153.0.8010.36. The vulnerability is rated high severity with a CVSS 3.1 score of 8.3, reflecting network attack vector, high impact on confidentiality, integrity, and availability, and requiring user interaction with high attack complexity.

Successful exploitation allows remote code execution outside the sandbox, potentially compromising the security boundaries of the browser. This could lead to full system compromise or unauthorized access to sensitive information. The vulnerability requires that the attacker has already compromised the renderer process and that the user interacts with a crafted HTML page.

A stable channel update for Google Chrome version 153.0.8010.36 has been released to address this vulnerability. Users and administrators should update to version 153.0.8010.36 or later to mitigate this issue. No additional mitigation steps are indicated by the vendor advisory.