CVE-2026-106413: Google Chrome Race Condition Vulnerability

CVE-2026-106413 Overview

CVE-2026-106413 is a race condition vulnerability in the Browser component of Google Chrome prior to version 155.0.8059.39. A remote attacker who has already compromised the renderer process can exploit the flaw to spoof user interface (UI) elements through a crafted HTML page. The weakness is classified under CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition. Google tracked the issue internally as Chromium security severity Low and resolved it in the Stable channel desktop update.

Critical Impact
An attacker who controls a compromised renderer can present spoofed browser UI elements to the user, enabling convincing phishing or security-prompt deception in otherwise trusted Chrome windows.

Affected Products

Google Chrome Desktop prior to 155.0.8059.39
Chromium-based browsers that share the vulnerable Browser-process code path
All supported desktop platforms (Windows, macOS, Linux) running pre-patch Chrome builds

Discovery Timeline

2026-10-06 - CVE-2026-106413 published to the National Vulnerability Database (NVD)
2026-10-07 - Last updated in NVD database

Technical Details for CVE-2026-106413

Vulnerability Analysis

The vulnerability is a race condition in the Chrome Browser process. The Browser process mediates privileged UI operations such as address bar updates, security indicators, and permission prompts on behalf of renderer processes. When specific UI-related events are processed concurrently, timing between validation and rendering of UI state can be manipulated. An attacker who already controls a renderer sends crafted messages or page content that wins the race, causing the Browser process to display UI elements that do not reflect the actual security state of the page.

Exploitation requires a prior renderer compromise, so this flaw is useful as a secondary step in a multi-stage attack chain. The impact is limited to confidentiality and availability of displayed UI information rather than direct code execution. Successful spoofing supports credential theft, consent-grant abuse, and user deception around downloads or extension installs.

Root Cause

The root cause is a time-of-check to time-of-use (TOCTOU) condition [CWE-367] in which the Browser process validates UI state at one point and renders it at another without an atomic guarantee. Concurrent IPC traffic from a malicious renderer can alter the observable state in the window between those operations. Full technical details are tracked in Chromium Issue Tracker #553336689.

Attack Vector

The attack is network-reachable but requires high attack complexity and user interaction. The adversary must first compromise a renderer process, typically through a separate renderer-side vulnerability or malicious web content. The attacker then serves a crafted HTML page that triggers the race condition and renders misleading UI chrome such as spoofed origin indicators, dialogs, or omnibox content. No verified public exploit or proof-of-concept is available at the time of writing.

Detection Methods for CVE-2026-106413

Indicators of Compromise

Chrome processes communicating with unexpected external domains following visits to untrusted HTML content
Browser crash reports or renderer sandbox violations preceding anomalous UI behavior reported by users
User reports of inconsistent address bar, permission prompt, or security indicator rendering

Detection Strategies

Inventory Chrome versions across endpoints and flag any installation below 155.0.8059.39
Correlate renderer crashes, sandbox escapes, and suspicious child-process behavior with subsequent credential submission events
Monitor browser telemetry for unexpected IPC traffic patterns originating from renderer processes

Monitoring Recommendations

Collect Chrome update and version telemetry centrally using endpoint management tooling
Alert on execution of Chrome binaries that do not match the approved patched version baseline
Enable browser crash and extension telemetry forwarding to your SIEM for correlation with phishing and credential-theft signals

How to Mitigate CVE-2026-106413

Immediate Actions Required

Update Google Chrome Desktop to version 155.0.8059.39 or later on all supported platforms
Force-restart Chrome after the update to ensure the patched Browser process is loaded
Verify Chromium-based third-party browsers have incorporated the upstream fix before trusting them as remediated

Patch Information

Google addressed the issue in the Stable channel update documented in the Google Chrome Desktop Update advisory. Administrators should push 155.0.8059.39 or later through enterprise update channels. Technical remediation details are tracked in Chromium Issue Tracker #553336689.

Workarounds

Enforce Chrome auto-update using the ChromeCleanupEnabled and update policies in enterprise management
Restrict browsing to trusted sites via web filtering until all endpoints are patched
Train users to validate sensitive actions, such as credential entry and permission grants, through secondary channels when UI prompts appear unexpectedly

bash

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

# Windows: query installed Chrome version from the registry
reg query "HKLM\Software\Google\Chrome\BLBeacon" /v version

# Enforce minimum version via Chrome Enterprise policy (example JSON)
# Place in the managed policies store for Chrome
{
  "TargetVersionPrefix": "155.0.8059.",
  "ComponentUpdatesEnabled": true,
  "DefaultBrowserSettingEnabled": true
}