CVE-2026-12439: Google Chrome Use After Free Vulnerability

CVE-2026-12439 Overview

CVE-2026-12439 is a use-after-free vulnerability [CWE-416] in the Digital Credentials component of Google Chrome. The flaw affects all Chrome desktop builds prior to version 149.0.7827.155 across Windows, macOS, and Linux. A remote attacker can trigger heap corruption by serving a crafted HTML page to a victim browser. Chromium engineers rated the underlying defect as Critical severity, while the CVE carries a CVSS 3.1 base score of 8.8. Successful exploitation requires user interaction, typically navigation to an attacker-controlled site. The condition can lead to arbitrary code execution within the renderer process and is a likely candidate for chaining with sandbox escapes.

Critical Impact
Remote attackers can corrupt heap memory and potentially execute code in the Chrome renderer process by luring users to a crafted web page.

Affected Products

Google Chrome versions prior to 149.0.7827.155
Chrome desktop builds on Microsoft Windows, Apple macOS, and Linux
Chromium-based browsers that consume the upstream Digital Credentials code paths

Discovery Timeline

2026-06-17 - CVE-2026-12439 published to NVD
2026-06-18 - Last updated in NVD database
2026-06 - Google releases fix in the Stable channel update for desktop, see the Google Chrome Desktop Update

Technical Details for CVE-2026-12439

Vulnerability Analysis

The vulnerability resides in Chrome's Digital Credentials API implementation, which brokers credential presentation requests between web origins and platform credential providers. A use-after-free condition arises when a heap-allocated object tied to a credential request is freed while another code path retains a dangling reference. When the dangling reference is dereferenced, the attacker can influence the contents of the reused memory region, producing controlled heap corruption. The bug is reachable from a web page via JavaScript that exercises the Digital Credentials interface, which is why network attack vector and user interaction apply.

Root Cause

The root cause is improper object lifetime management within the Digital Credentials subsystem. Asynchronous request handling and renderer-side state transitions allow an object to be released before all consumers have completed their work. Chromium's reference for this issue is tracked in the Chromium Issue Tracker Entry. This class of defect (CWE-416) is recurrent in browser engines that manage complex object graphs across IPC boundaries.

Attack Vector

An attacker hosts a malicious HTML page that invokes Digital Credentials APIs in a sequence designed to free and reuse the target object. The victim must visit the page or open it through an embedded resource. Once heap corruption is achieved, the attacker can pivot toward arbitrary code execution in the renderer. Coupling this primitive with a separate sandbox escape would extend impact beyond the renderer to the host operating system.

No public proof-of-concept or in-the-wild exploitation has been reported. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog, and the EPSS probability is 0.3%.

Detection Methods for CVE-2026-12439

Indicators of Compromise

Chrome renderer process crashes referencing the Digital Credentials code paths or generic heap corruption signatures
Outbound connections from chrome.exe to recently registered or low-reputation domains immediately preceding renderer crashes
Unexpected child processes spawned by Chrome shortly after navigation to an untrusted page

Detection Strategies

Inventory Chrome installations and flag any host running a version earlier than 149.0.7827.155
Correlate Windows Error Reporting and macOS CrashReporter telemetry for repeated Chrome renderer faults across endpoints
Hunt browser telemetry for pages invoking the Digital Credentials API from unfamiliar origins

Monitoring Recommendations

Forward endpoint process, network, and crash telemetry to a centralized analytics platform for retrospective hunting
Alert on Chrome processes loading unexpected modules or initiating shellcode-like memory regions
Track DNS and web proxy logs for users visiting newly observed domains followed by browser instability

How to Mitigate CVE-2026-12439

Immediate Actions Required

Update Google Chrome on all Windows, macOS, and Linux endpoints to version 149.0.7827.155 or later
Restart Chrome after applying the update to ensure the patched binary is in use
Apply equivalent fixes to other Chromium-based browsers as their vendors publish updates

Patch Information

Google resolved the issue in the Chrome Stable channel release documented in the Google Chrome Desktop Update. Enterprise administrators should push the update through Chrome Browser Cloud Management, Group Policy, MDM, or their standard software distribution pipeline. Verify deployment by querying chrome://version or the installed package version on managed endpoints.

Workarounds

Restrict access to untrusted websites through web proxy or DNS filtering until patches are applied
Disable or restrict the Digital Credentials API via enterprise policy where supported
Use site isolation and enforce least-privilege user accounts to limit the impact of renderer compromise

bash

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

# Windows: query installed Chrome version via registry
reg query "HKLM\SOFTWARE\Google\Chrome\BLBeacon" /v version

# macOS: read the bundle version
defaults read "/Applications/Google Chrome.app/Contents/Info.plist" CFBundleShortVersionString