CVE-2026-4451: Google Chrome RCE Vulnerability

CVE-2026-4451 Overview

CVE-2026-4451 is an input validation vulnerability in the Navigation component of Google Chrome versions prior to 146.0.7680.153. The flaw stems from insufficient validation of untrusted input, classified as [CWE-20]. A remote attacker who has already compromised the renderer process can leverage a crafted HTML page to attempt a sandbox escape. Google rates the Chromium security severity as High. The issue affects Chrome on Windows, macOS, and Linux platforms.

Critical Impact
An attacker chaining this flaw with a renderer compromise can break out of the Chrome sandbox, gaining the ability to execute code with broader privileges on the host system.

Affected Products

Google Chrome prior to 146.0.7680.153 on Microsoft Windows
Google Chrome prior to 146.0.7680.153 on Apple macOS
Google Chrome prior to 146.0.7680.153 on Linux

Discovery Timeline

2026-03-20 - CVE-2026-4451 published to the National Vulnerability Database
2026-03-20 - Last updated in NVD database

Technical Details for CVE-2026-4451

Vulnerability Analysis

The vulnerability resides in the Navigation subsystem of Chromium, which coordinates how browser processes handle URL transitions, frame loads, and cross-origin navigations. Insufficient validation of untrusted input allows malicious data originating from a compromised renderer to influence trusted browser-process logic. Because the Navigation stack mediates privileged operations between the sandboxed renderer and the higher-privilege browser process, weakened input checks create a path for sandbox escape.

Root Cause

The root cause is improper validation of untrusted input (CWE-20) flowing into navigation handling. Chrome's multi-process architecture assumes the browser process treats data from renderer processes as untrusted. When validation logic is incomplete, a renderer under attacker control can submit malformed or unexpected navigation parameters that bypass security checks intended to enforce the renderer-browser boundary.

Attack Vector

Exploitation requires two stages. First, the attacker must compromise the Chrome renderer process, typically through a prior memory corruption or type confusion bug triggered by a crafted HTML page. Second, the attacker abuses the navigation validation gap to escalate out of the sandbox. The attack is delivered remotely over the network and requires user interaction such as visiting an attacker-controlled web page. No specific public proof-of-concept code is available, and the EPSS probability stands at 0.052%.

The vulnerability mechanism is described in the Chromium Issue Tracker #487768779 and the Google Chrome Stable Update advisory.

Detection Methods for CVE-2026-4451

Indicators of Compromise

Chrome browser processes spawning unexpected child processes outside of standard renderer or utility process patterns.
Outbound connections from chrome.exe or its helpers to unfamiliar domains immediately after navigation events.
Renderer process crashes followed by anomalous file or registry writes from the browser process.

Detection Strategies

Inventory endpoints to identify Chrome installations running versions below 146.0.7680.153 and flag them for patching.
Monitor for renderer-to-browser process anomalies, including unexpected inter-process communication patterns.
Correlate browser process behavior with web traffic logs to identify suspicious HTML payloads delivered prior to crashes.

Monitoring Recommendations

Enable enterprise telemetry from Chrome via the Chrome Browser Cloud Management console to collect crash and update status.
Forward endpoint process telemetry to a centralized analytics platform for behavioral analysis of browser process trees.
Alert on Chrome version drift across managed fleets to ensure timely identification of unpatched hosts.

How to Mitigate CVE-2026-4451

Immediate Actions Required

Update Google Chrome to version 146.0.7680.153 or later on all Windows, macOS, and Linux endpoints.
Verify automatic updates are enabled and not blocked by enterprise policy or network restrictions.
Restart Chrome on all managed endpoints after the update to ensure the patched binaries are loaded.

Patch Information

Google released the fix in the Chrome Stable channel update published on March 18, 2026. Administrators should consult the Google Chrome Stable Update advisory for full release notes and confirm deployment of build 146.0.7680.153 or higher.

Workarounds

Restrict browsing to trusted sites using enterprise URL filtering until patches are deployed.
Deploy site isolation and strict Content Security Policy enforcement to reduce renderer compromise risk.
Use application allowlisting to limit child processes that Chrome can spawn on managed endpoints.

bash

# Verify installed Chrome version on Linux
google-chrome --version

# Force update check on Windows (PowerShell)
Start-Process "C:\Program Files\Google\Chrome\Application\chrome.exe" -ArgumentList "--check-for-update-interval=1"

# macOS: trigger Google Software Update
/Library/Google/GoogleSoftwareUpdate/GoogleSoftwareUpdate.bundle/Contents/Resources/GoogleSoftwareUpdateAgent.app/Contents/MacOS/GoogleSoftwareUpdateAgent -runMode oneshot