External risk intelligence

Google Chrome Link Following Vulnerability Allows Arbitrary Code Execution

CVE advisorySeverity: CRITICAL (CVSS 9.6)

CVE-2026-126859

This vulnerability affects a web browser and requires a user to interact with a crafted HTML page. Because it is a client-side application vulnerability rather than a server-side service, edge gateway, or network-accessible management interface, it is not considered internet-facing in the context of persistent, reachable attack surfaces.

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 vulnerability has been identified in Google Chrome that could allow attackers to execute code outside the browser's security sandbox. This occurs when a user is tricked into visiting a malicious webpage. While the technical details involve bypassing security measures, the core risk is the potential for unauthorized code execution.

  • Malicious pages can bypass browser security.
  • Understand potential for remote code execution.
  • Confirm relevance and evaluate exposure.

Attack Path

How an attacker could exploit the issue

An attacker could trick a user into visiting a malicious webpage. This page would then exploit a flaw in how Google Chrome handles file links, allowing code to run outside the browser's safe environment. This could potentially let the attacker take control of the user's computer.

  • Requires a user to click a link.
  • Malicious HTML page.
  • Arbitrary code execution outside sandbox.

Live Threat

Current exploitation, exposure, and threat context

A crafted HTML page could allow an attacker to execute code outside the browser's sandbox on a user's system, when supported by social engineering.

  • User system.
  • Social engineering interaction.
  • Arbitrary code execution.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability in Google Chrome requires a user to interact with a malicious HTML page to execute code outside the sandbox. Technical leaders should direct their security teams to identify instances of the affected browser, assess user exposure and business criticality, and coordinate with vendor management for a planned update.

  • Own the issue through browser deployment teams.
  • Verify user exposure and criticality.
  • Coordinate vendor update and user guidance.

Supplementary metadata

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.

Frequently asked questions

What is Google Chrome and how does its sandbox protect me?

Google Chrome is a web browser built on the Chromium engine, designed to fetch and display internet content. It uses a security sandbox—a restricted environment—to isolate web code from your computer's operating system. This ensures that even if a malicious webpage tries to act harmfully, it remains contained and unable to modify system files or execute unauthorized programs on your machine.

What does CWE-59 mean for CVE-2026-126859?

This CVE involves a vulnerability classified as CWE-59, which refers to improper handling of symbolic links (link following). In this specific case, the browser is tricked into following a file link it shouldn't have accessed. This mistake allows the attacker to break out of the browser's sandbox environment, enabling them to execute arbitrary code directly on your local system instead of being confined to the browser's restricted process.

How does an attacker trigger this vulnerability?

The attack requires a user to perform a specific action: visiting a crafted, malicious HTML page, typically via social engineering. The bug is not triggered by simply having the browser installed or running in the background. It also does not trigger through normal web browsing on legitimate sites; the malicious site must be intentionally designed to exploit the way the browser manages file system links to gain unauthorized control.

Is this vulnerability internet-facing?

According to Halo Surface Signal, this is not considered internet-facing. Because it is a client-side application vulnerability, it does not act like a server-side service or a network-accessible management interface that is persistently reachable. While a user must navigate to a harmful site, the browser itself does not expose an open, external attack surface that is constantly listening for remote, unsolicited connections.

What is the recommended first step to respond to this issue?

Your primary goal should be to ensure all systems are running an updated version of Google Chrome, specifically version 157.0.8103.78 or later, which addresses this flaw. Coordinate with your software deployment or IT teams to track browser versions across your organization. Until updates are applied, remind users to remain cautious of clicking links from untrusted sources, as the vulnerability relies on user interaction to succeed.

References