CVE-2026-106296: Chrome on Mac Privilege Escalation Flaw

CVE-2026-106296 Overview

CVE-2026-106296 is an improper privilege management vulnerability [CWE-269] in the user interface of Google Chrome on macOS. The flaw affects Chrome versions prior to 155.0.8059.39. A remote attacker who successfully lures a user to a crafted HTML page can bypass system access restrictions. Exploitation requires social engineering to coerce the victim into interacting with the malicious content. Chromium classifies the security severity of this issue as Low.

Critical Impact
An attacker can bypass macOS system access restrictions through the Chrome UI when a user is tricked into visiting a crafted HTML page.

Affected Products

Google Chrome on macOS prior to version 155.0.8059.39
Chromium-based browsers on macOS that incorporate the affected UI code
Downstream distributions bundling vulnerable Chrome builds on macOS

Discovery Timeline

2026-10-06 - CVE CVE-2026-106296 published to NVD
2026-10-06 - Last updated in NVD database

Technical Details for CVE-2026-106296

Vulnerability Analysis

The vulnerability resides in Chrome's UI layer on macOS. Chrome fails to properly enforce privilege boundaries when rendering specific UI elements driven by remote content. An attacker crafts an HTML page that manipulates the browser interface to perform actions that should require elevated or user-confirmed privileges. The result is a bypass of macOS system access restrictions enforced through Chrome's security surface. Exploitation does not grant arbitrary code execution on its own but weakens the browser's role as a trust boundary against untrusted web content.

Root Cause

The root cause is improper privilege management [CWE-269] in UI handling code specific to the macOS build of Chrome. Privilege checks that should gate access to protected system functionality are either missing or improperly scoped. This allows web-origin content to influence UI-driven actions beyond the privileges normally granted to a remote page.

Attack Vector

The attack vector is remote and web-based with required user interaction. An attacker hosts a crafted HTML page and uses social engineering to drive the victim to visit the page using an unpatched Chrome build on macOS. The page triggers UI interactions that bypass system access restrictions. No authentication is required on the target.

No verified public proof-of-concept is available. See the Chromium Issue Tracker #540078886 and the Google Chrome Stable Update for technical details.

Detection Methods for CVE-2026-106296

Indicators of Compromise

Chrome processes on macOS endpoints reporting a version string earlier than 155.0.8059.39.
Browser navigation events to unexpected or newly registered domains immediately followed by prompts to grant system access.
Unusual spawning of macOS privilege-related dialogs or TCC prompts initiated from a browser session.

Detection Strategies

Inventory installed Chrome versions across macOS fleets and flag any instance below 155.0.8059.39.
Correlate web proxy logs with endpoint telemetry to identify users visiting newly observed domains that trigger browser UI interactions.
Monitor for process lineage where Chrome helper processes invoke macOS system APIs tied to protected resources.

Monitoring Recommendations

Enable browser management telemetry through Chrome Enterprise reporting to capture version compliance and extension state.
Forward macOS endpoint and browser logs into a centralized data lake for correlation with threat intelligence on social engineering campaigns.
Alert on repeated user prompts related to macOS access controls originating from browser-rendered content.

How to Mitigate CVE-2026-106296

Immediate Actions Required

Update Google Chrome on all macOS endpoints to version 155.0.8059.39 or later.
Restart Chrome after update to ensure the patched binaries are loaded into memory.
Validate deployment coverage by querying endpoint inventory for Chrome version strings.

Patch Information

Google addressed this vulnerability in the Chrome Stable channel update for desktop. Install Chrome 155.0.8059.39 or later on macOS. Refer to the Google Chrome Stable Update advisory and Chromium Issue Tracker #540078886 for release details.

Workarounds

Enforce user awareness training focused on social engineering lures that direct users to unfamiliar web pages.
Restrict browsing to known-good domains using DNS filtering or secure web gateway policies until patching completes.
Apply Chrome Enterprise policies that reduce exposure to untrusted sites and limit permission prompts.

bash

# Verify Chrome version on macOS
/Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --version

# Force Chrome auto-update via Google Software Update
/Library/Google/GoogleSoftwareUpdate/GoogleSoftwareUpdate.bundle/Contents/Resources/GoogleSoftwareUpdateAgent.app/Contents/MacOS/GoogleSoftwareUpdateAgent -runMode oneshot