CVE-2026-12440: Google Chrome Use After Free Vulnerability

CVE-2026-12440 Overview

CVE-2026-12440 is a use-after-free vulnerability [CWE-416] in the DigitalCredentials component of Google Chrome on Windows. The flaw affects Chrome versions prior to 149.0.7827.155. A remote attacker can serve a crafted HTML page to trigger memory corruption inside the renderer process. Successful exploitation can lead to a sandbox escape, giving an attacker code execution outside the Chrome renderer sandbox. Google rated the underlying Chromium issue as Critical severity.

Critical Impact
Remote attackers can escape the Chrome sandbox on Windows through a crafted web page, enabling code execution in a higher-privilege context with only user interaction required.

Affected Products

Google Chrome on Windows prior to 149.0.7827.155
Microsoft Windows hosts running vulnerable Chrome builds
Chromium-based browsers sharing the affected DigitalCredentials code path

Discovery Timeline

2026-06-17 - CVE-2026-12440 published to NVD
2026-06-18 - Last updated in NVD database

Technical Details for CVE-2026-12440

Vulnerability Analysis

The vulnerability resides in Chrome's DigitalCredentials API implementation, which exposes browser-mediated credential presentation flows to web origins. A use-after-free condition occurs when the component continues to reference a heap object after it has been freed. An attacker who controls the lifecycle of the underlying credential request object can reclaim the freed allocation with attacker-influenced data.

Because the bug is reachable from an HTML page, exploitation requires only that a victim visit a malicious site or load attacker-controlled content inside an embedded frame. The flaw chains memory corruption in the renderer with a sandbox escape, meaning a single crafted page can break out of Chrome's renderer sandbox on Windows.

The issue is tracked in the Chromium Issue Tracker Entry and was addressed in the Google Chrome Update Announcement.

Root Cause

The root cause is improper object lifetime management inside the DigitalCredentials code. A reference to a heap-allocated object outlives the deallocation of that object. When the freed memory is reused, subsequent dereferences operate on attacker-controlled contents, yielding a primitive suitable for type confusion or control-flow hijack.

Attack Vector

The attack is network-reachable and requires user interaction, such as visiting a malicious URL. The attacker hosts a crafted HTML page that exercises the DigitalCredentials API in a sequence that frees an internal object while a dangling reference remains. The attacker then sprays the heap to reoccupy the freed slot before the dangling pointer is used. Successful exploitation pivots from renderer compromise to sandbox escape, executing code in a less-restricted Chrome process on Windows.

No public proof-of-concept or exploit is currently available, and the CVE is not listed in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2026-12440

Indicators of Compromise

Chrome renderer or utility process crashes referencing DigitalCredentials symbols in Windows Error Reporting (WER) data.
Unexpected child processes spawned by chrome.exe shortly after browsing activity, particularly processes outside the standard Chrome process tree.
Outbound connections from Chrome processes to newly registered or low-reputation domains hosting credential-themed pages.

Detection Strategies

Inventory Chrome installations and flag any Windows endpoint running a version below 149.0.7827.155.
Hunt for Chrome process crashes with exception codes consistent with use-after-free corruption, correlated with recent browsing history.
Monitor for post-exploitation behaviors such as Chrome spawning cmd.exe, powershell.exe, or writing executables to user-writable paths.

Monitoring Recommendations

Forward Chrome crash telemetry and Windows Error Reporting events to a central log platform for analysis.
Alert on browser child-process anomalies, including unsigned binaries launched from Chrome's process tree.
Track Chrome version drift across the fleet using endpoint management telemetry to surface unpatched hosts.

How to Mitigate CVE-2026-12440

Immediate Actions Required

Update Google Chrome on all Windows endpoints to version 149.0.7827.155 or later.
Restart browsers after updating to ensure the patched binaries are loaded into memory.
Apply equivalent updates to Chromium-based browsers (Edge, Brave, Opera, Vivaldi) once vendor builds incorporating the fix are released.

Patch Information

Google released the fix in the Chrome Stable channel for desktop. Refer to the Google Chrome Update Announcement for the official release notes and the Chromium Issue Tracker Entry for the underlying bug record.

Workarounds

Enforce automatic Chrome updates through enterprise policy until patched builds are confirmed deployed.
Restrict access to the Digital Credentials API via the DigitalCredentialsApiEnabled enterprise policy on managed Windows fleets where the feature is not required.
Use web filtering to block access to untrusted or newly observed domains until patching is complete.

bash

# Example: enforce Chrome update policy on Windows via Group Policy registry keys
reg add "HKLM\Software\Policies\Google\Update" /v UpdateDefault /t REG_DWORD /d 1 /f
reg add "HKLM\Software\Policies\Google\Update" /v AutoUpdateCheckPeriodMinutes /t REG_DWORD /d 60 /f
reg add "HKLM\Software\Policies\Google\Chrome" /v DigitalCredentialsApiEnabled /t REG_DWORD /d 0 /f