External risk intelligence

Google Chrome Sandbox Escape via Use After Free Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.6)

CVE-2026-11671

This vulnerability exists within a web browser client. Exploitation requires a user to navigate to a specifically crafted HTML page. It is not a network-accessible service, gateway, or internet-facing infrastructure component; rather, it is a client-side application vulnerability that requires user interaction to reach the vulnerable code.

Use After Free

Google Chrome

before 149.0.7827.103

Halo Surface Signal: 1 out of 5 — much less likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A security flaw has been identified in Google Chrome that could allow an attacker to break out of the browser's security sandbox. This is possible through a specially crafted web page, and while it requires user interaction, it carries a high severity rating. The primary concern is to confirm if our organization utilizes the affected version of Chrome and if there's any exposure.

Browser flaw allows sandbox escape.
High severity, requires user interaction.
Confirm relevance and exposure.

Attack Path

How an attacker could exploit the issue

An attacker could trick a user into visiting a malicious website. This website would contain a specially crafted HTML page designed to exploit a use-after-free vulnerability in Chrome's navigation component. If successful, this could allow the attacker to break out of the browser's sandbox, potentially leading to broader system compromise.

No user authentication required.
Malicious HTML page.
Sandbox escape and system compromise.

Live Threat

Current exploitation, exposure, and threat context

A use-after-free vulnerability in Chrome's navigation could allow a remote attacker to escape the browser's sandbox when a user visits a malicious HTML page. This could potentially impact the confidentiality and integrity of data processed by the browser.

Browser sandbox escape.
Via a crafted HTML page.
Potential data compromise.

Operational Fix

Recommended remediation, mitigation, and detection steps

In a real-world scenario, the Chrome browser's use-after-free vulnerability would primarily concern application owners responsible for user-facing applications and potentially platform teams managing the underlying operating systems. The initial practical move involves identifying all instances of Chrome, determining their reachability and business criticality, and then locating the accountable owners to plan remediation based on risk, possibly involving vendor coordination for updates.

Identify Chrome instances and owners.
Verify browser reachability and criticality.
Plan risk-based remediation or updates.

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.

Free EASM Trial See How Signal Works

Frequently asked questions

What is Google Chrome and how is it used?

Google Chrome is a widely used web browser that renders HTML content and executes web applications. It includes a security sandbox designed to isolate browser processes from the underlying operating system. This isolation ensures that even if a malicious website compromises the browser, the rest of the computer remains protected.

What does use-after-free mean for CVE-2026-11671?

A use-after-free is a memory corruption weakness, classified as CWE-416. It happens when software continues to use a memory location after it has been cleared or freed. In the context of this CVE, it occurs within the browser's navigation component. An attacker can exploit this flawed memory management to manipulate browser operations and potentially bypass the security sandbox.

How is this Chrome vulnerability triggered?

The flaw is triggered when a user navigates to a specifically crafted HTML page designed by an attacker to exploit the memory error. It does not trigger by simply having the browser installed or running in the background. The interaction requires the browser to process malicious code embedded within a website, which then initiates the flawed navigation process.

Is CVE-2026-11671 a concern for my network?

According to Halo Surface Signal, this is a client-side browser issue, not an internet-facing server or gateway vulnerability. While the security impact is high, the vulnerability resides on individual user devices rather than infrastructure. Your risk depends on whether your users visit untrusted or malicious websites while using an outdated version of the browser.

How do I address this Chrome vulnerability?

The most effective way to secure your environment is to update Google Chrome to version 149.0.7827.103 or newer. Begin by identifying systems running older versions of Chrome across your organization. Once identified, prioritize these systems for browser updates to ensure users are protected by the latest security patches provided by the vendor.

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.