External risk intelligence

Chrome Renderer Sandbox Escape Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.6)

CVE-2026-11047

The vulnerability affects a web browser used by end users to access the public internet. While the attack requires a user to navigate to a crafted HTML page, the nature of web browsers as primary tools for internet browsing makes exposure to malicious content on the public web a common and expected deployment scenario.

Google Chrome

before 149.0.7827.53

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A security issue in Google Chrome on Windows could allow an attacker to escape the browser's security sandbox, potentially impacting user systems if they visit a compromised web page. The primary concern is confirming if this specific vulnerability is relevant to your environment.

Sandbox escape in Chrome browser.
Confirms browser security as a key focus.
Assess exposure and confirm relevance.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by tricking a user into visiting a malicious HTML page. This would allow them to break out of the browser's security sandbox and potentially gain control of the user's system. The vulnerability is present in Google Chrome on Windows before version 149.0.7827.53.

Requires a user to visit a malicious page.
Triggered by a crafted HTML page.
Risk of sandbox escape and system compromise.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability could allow an attacker who has already compromised the browser's rendering process to escape the sandbox when a user visits a specially crafted HTML page. This could potentially lead to broader system access.

User's system data.
Visiting a malicious web page.
Compromise of system integrity.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability in Google Chrome could allow a sandboxed renderer process to escape to the operating system on Windows. Responsibility for remediation typically falls to teams managing end-user computing, application deployment, and browser security policies. The immediate first step is to identify all instances of the affected browser version, assess their reachability and criticality, and confirm the accountable owner for Chrome updates before planning a coordinated remediation.

End-user computing and platform teams own remediation.
Verify Chrome browser exposure and criticality.
Plan coordinated updates or vendor coordination.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is Google Chrome on Windows?

Google Chrome is a widely used web browser that runs on the Windows operating system. It acts as the primary interface for users to access the public internet, rendering HTML, CSS, and JavaScript content. Because it processes complex data from potentially untrusted web sources, it employs a security sandbox—a restricted environment designed to contain the browser's processes and prevent them from directly interacting with or modifying the underlying host computer's operating system.

What does CVE-2026-11047 mean for browser security?

This vulnerability is classified as CWE-20, or Improper Input Validation. In plain terms, the browser fails to correctly verify the information it receives when processing web content. Because the browser's sandbox is supposed to be a hardened wall, this flaw allows a malicious actor who has already subverted the browser's internal rendering process to bypass those restrictions, effectively 'escaping' the container to gain unintended control over the computer.

How does an attacker trigger this sandbox escape?

An attacker triggers the vulnerability by luring a user to a specially crafted HTML page. The flaw cannot be triggered simply by having the browser installed or running in the background; it requires the user to actively navigate to the malicious content. If a user does not visit the specific web page designed to exploit this input validation error, the sandbox remains intact and the attack path is not initiated.

Is my system at risk according to Halo Surface Signal?

Halo Surface Signal labels this as likely relevant because web browsers are inherently designed to access the public internet. Since the primary attack vector is a malicious web page, any system running an outdated version of Chrome is potentially exposed whenever a user browses the web. The risk is tied to the browser's role as a gateway to the internet, making it a natural focal point for attackers looking to leverage web-based threats.

How do I respond to this Chrome vulnerability?

The most effective way to address this issue is to update your browser. You should confirm the current version of Google Chrome across your environment and identify any instances running versions prior to 149.0.7827.53. Coordinating with the teams responsible for end-user computing and browser policy is the standard approach to ensuring that these updates are applied, thereby closing the security gap that allows the sandbox escape.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.