CVE-2026-14406: Google Chrome V8 Information Disclosure

CVE-2026-14406 Overview

CVE-2026-14406 is an out-of-bounds read vulnerability in the V8 JavaScript engine used by Google Chrome. The flaw affects Chrome versions prior to 150.0.7871.46 and can be triggered through a crafted Chrome extension. An attacker who convinces a user to install a malicious extension can read data beyond intended memory boundaries. This exposure enables retrieval of potentially sensitive information from process memory. Google classified the Chromium security severity as Medium.

Critical Impact
Attackers can extract sensitive data from V8 process memory through a malicious Chrome extension, potentially exposing browsing data, credentials cached in memory, or cross-origin content.

Affected Products

Google Chrome desktop versions prior to 150.0.7871.46
Chromium-based browsers embedding the vulnerable V8 engine
Chrome installations with untrusted extensions installed

Discovery Timeline

2026-07-01 - CVE-2026-14406 published to NVD
2026-07-02 - Last updated in NVD database

Technical Details for CVE-2026-14406

Vulnerability Analysis

The vulnerability is an out-of-bounds read [CWE-125] within V8, the JavaScript and WebAssembly engine that powers Chrome. V8 executes code in the renderer process and enforces sandboxed memory boundaries for scripts and extensions. When a crafted extension exercises a specific code path in V8, the engine reads memory outside the intended buffer bounds. The disclosed data resides in the same renderer process, meaning it can include JavaScript heap contents, string data, or other allocations. The attack requires user interaction to install the malicious extension, but no additional privileges once installed.

Root Cause

The root cause is missing or incorrect bounds validation when V8 handles a specific input pattern reachable through extension APIs. V8 accesses memory adjacent to a valid object without confirming the read offset remains within the allocated region. This allows the extension's JavaScript to observe memory contents that should be inaccessible.

Attack Vector

Exploitation requires distributing a malicious extension and convincing a user to install it through the Chrome Web Store or developer mode. Once installed, the extension executes JavaScript that triggers the vulnerable V8 code path. The attacker then reads leaked bytes back through extension messaging or exfiltrates them over the network. The attack complexity is high because the attacker must satisfy specific memory layout conditions to obtain useful data.

No verified proof-of-concept code has been published. See the Chromium Issue Tracker Entry for restricted technical details and the Google Chrome Update Announcement for release notes.

Detection Methods for CVE-2026-14406

Indicators of Compromise

Chrome extensions installed outside the enterprise-approved allowlist, particularly recently sideloaded or developer-mode extensions.
Extensions requesting broad host permissions or scripting and webRequest privileges without a clear business need.
Outbound network connections from Chrome renderer processes to uncategorized or newly registered domains.

Detection Strategies

Inventory installed Chrome extensions across managed endpoints and compare identifiers against a known-good baseline.
Monitor Chrome version telemetry to identify hosts running builds earlier than 150.0.7871.46.
Alert on installation of extensions from sources other than the Chrome Web Store or from users with developer mode enabled.

Monitoring Recommendations

Enable Chrome Enterprise reporting to stream extension install events and browser version data to a central log store.
Correlate extension activity with process memory anomalies and renderer crash telemetry.
Review DNS and proxy logs for extension-driven exfiltration patterns tied to renderer processes.

How to Mitigate CVE-2026-14406

Immediate Actions Required

Update Google Chrome to version 150.0.7871.46 or later on all managed endpoints.
Audit installed extensions and remove any that are unapproved, unsigned, or unnecessary.
Restrict extension installation to an enterprise-managed allowlist through Chrome policy.

Patch Information

Google released the fix in Chrome Stable channel version 150.0.7871.46. Restart the browser after updating to ensure the patched V8 engine is loaded. Refer to the Google Chrome Update Announcement for full release details.

Workarounds

Enforce the ExtensionInstallAllowlist and ExtensionInstallBlocklist policies to prevent unauthorized extension installs.
Disable developer mode extensions through the DeveloperToolsAvailability policy where feasible.
Educate users to install extensions only from verified publishers and to remove unused extensions.

bash

# Chrome policy example (Linux managed policies JSON)
{
  "ExtensionInstallBlocklist": ["*"],
  "ExtensionInstallAllowlist": [
    "approved_extension_id_1",
    "approved_extension_id_2"
  ],
  "DeveloperToolsAvailability": 2
}