CVE-2026-113009 Overview
CVE-2026-113009 is a use-after-free vulnerability in the WindowControlsOverlay component of Google Chrome versions prior to 156.0.8078.47. A remote attacker can execute arbitrary code inside the Chrome sandbox by serving a crafted HTML page to a target user. The flaw is tracked as CWE-416: Use After Free and requires user interaction, such as visiting a malicious website. Chromium classifies the security severity as Medium, while the NVD scored the issue as High. Google addressed the issue in the stable channel update published on the Chrome Releases blog.
Critical Impact
Successful exploitation lets a remote attacker execute arbitrary code within the renderer sandbox, enabling follow-on attacks that chain with sandbox escapes to achieve full browser compromise.
Affected Products
- Google Chrome Desktop (Windows, macOS, Linux) prior to 156.0.8078.47
- Chromium-based builds that embed the vulnerable WindowControlsOverlay code
- Downstream browsers packaging Chromium versions earlier than 156.0.8078.47
Discovery Timeline
- 2026-10-20 - CVE-2026-113009 published to NVD
- 2026-10-21 - Last updated in NVD database
Technical Details for CVE-2026-113009
Vulnerability Analysis
The vulnerability resides in the WindowControlsOverlay implementation, a Chrome feature that lets installed Progressive Web Apps (PWAs) draw into the title bar region. A use-after-free condition occurs when the renderer references an object tied to the overlay after it has been released. An attacker who controls the lifecycle of the overlay object through crafted HTML and JavaScript can reclaim the freed memory and influence subsequent reads or writes.
Because the bug lives inside the renderer process, exploitation yields code execution confined to the Chrome sandbox. Attackers typically chain this class of flaw with a sandbox escape to achieve code execution on the host. See the Chromium Issue Tracker Entry for the upstream bug record.
Root Cause
The root cause is improper object lifetime management in the WindowControlsOverlay code path. A reference to a freed C++ object remains reachable from script-exposed APIs, violating memory safety guarantees. Attackers trigger the free, reallocate the memory with attacker-controlled data, and then invoke an operation that dereferences the stale pointer.
Attack Vector
Exploitation is remote and requires user interaction. The victim must load a crafted HTML page that exercises the overlay API sequence needed to trigger the dangling reference. No privileges or credentials are required on the target. The attacker-controlled page can be delivered through phishing links, malicious advertisements, or compromised websites.
No public proof-of-concept or exploit code is listed for CVE-2026-113009 at the time of writing. See the Google Chrome Stable Update for vendor-published details.
Detection Methods for CVE-2026-113009
Indicators of Compromise
- Chrome renderer process crashes with signatures referencing WindowControlsOverlay or related Blink objects
- Outbound connections from browser processes to newly registered or low-reputation domains following a page visit
- Unexpected child processes spawned by chrome.exe or Google Chrome Helper (Renderer) on macOS
Detection Strategies
- Inventory installed Chrome versions across the fleet and alert on any build earlier than 156.0.8078.47
- Correlate browser crash telemetry with web proxy logs to identify URLs that consistently precede renderer faults
- Hunt for anomalous process trees originating from the browser, including script interpreters or LOLBins launched by renderer processes
Monitoring Recommendations
- Ingest endpoint and browser telemetry into a centralized data lake to retain visibility across renderer crashes and network egress
- Monitor for suspicious post-exploitation behavior such as credential access, token theft, or persistence attempts following browser activity
- Track Chrome auto-update status and surface endpoints where updates are blocked or delayed
How to Mitigate CVE-2026-113009
Immediate Actions Required
- Update Google Chrome to version 156.0.8078.47 or later on all desktop operating systems
- Restart Chrome after update to ensure patched binaries are loaded into memory
- Patch Chromium-based browsers and embedded frameworks once vendors release aligned updates
Patch Information
Google released the fix in the Chrome stable channel update documented at the Google Chrome Stable Update advisory. Administrators should confirm that managed deployments receive the update through Chrome Browser Cloud Management, Group Policy, or MDM-driven update channels. The upstream fix is tracked in the Chromium Issue Tracker Entry.
Workarounds
- Enforce Chrome auto-update policies and block execution of outdated browser versions until the patch is applied
- Restrict installation and use of PWAs that request the window-controls-overlay display mode until endpoints are updated
- Apply web filtering and DNS controls to limit exposure to untrusted sites during the patch window
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
