CVE-2026-113009 in Chrome
Summary
by MITRE • 10/21/2026
Use after free in WindowControlsOverlay in Google Chrome prior to 156.0.8078.47 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: Medium)
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 10/21/2026
The vulnerability identified as a use-after-free condition within the WindowControlsOverlay component of Google Chrome represents a critical memory safety flaw that compromises the integrity of the browser's rendering engine prior to version 156.0.8078.47. This specific defect arises from improper management of object lifecycles during the handling of window control overlays, which are user interface elements used in progressive web applications and certain native-like browsing experiences. When a crafted HTML page triggers the creation or destruction of these overlay components under specific timing conditions, the browser fails to properly invalidate pointers or references to the underlying memory structures before they are deallocated. Consequently, subsequent operations that interact with these stale references access freed memory regions, leading to undefined behavior within the sandboxed renderer process.
From a technical perspective, this flaw falls squarely under CWE-416, which classifies use-after-free errors as situations where code continues to use pointers after freeing them, often resulting in crashes or arbitrary code execution. The exploitation of this vulnerability requires an attacker to host a specially crafted HTML page that manipulates the lifecycle events of the WindowControlsOverlay API. By carefully orchestrating memory allocation and deallocation patterns through JavaScript interactions with the overlay components, an attacker can achieve heap corruption. This corruption allows for the overwriting of adjacent memory structures or control flow data, which can be leveraged to redirect execution paths within the renderer process. Although Chrome employs multiple layers of sandboxing designed to contain such exploits, successful exploitation in this context could potentially allow a remote attacker to execute arbitrary code inside the restricted environment of the browser's rendering engine.
The operational impact of this vulnerability is significant due to its potential for remote code execution via standard web browsing activities. A user visiting a malicious website containing the crafted HTML payload would trigger the vulnerable code path without any additional interaction beyond loading the page, depending on the specific exploit chain developed by an attacker. While the sandbox provides substantial protection against direct system-level compromise, breaking out of the renderer sandbox remains a primary objective for advanced persistent threats and state-sponsored actors. If the use-after-free condition is chained with other vulnerabilities or exploited through sophisticated heap spraying techniques, it may lead to arbitrary code execution outside the sandbox, granting full control over the victim's machine. The Chromium security team has classified this issue as medium severity, reflecting both the complexity of exploitation within the modern Chrome architecture and the potential for severe consequences if successful.
Mitigation strategies primarily involve immediate software updates to ensure that all instances of Google Chrome are upgraded to version 156.0.8078.47 or later, where these memory management issues have been resolved through rigorous code audits and fuzzing efforts. For organizations managing large deployments, automated patch management systems should be configured to prioritize this update due to the remote nature of the exploit vector. Additionally, security teams can employ browser hardening techniques such as disabling JavaScript execution on untrusted domains or utilizing content security policies that restrict access to potentially dangerous APIs like WindowControlsOverlay if they are not strictly required for business operations. Monitoring network traffic and endpoint detection systems for anomalous behavior associated with renderer process crashes or memory corruption events can also provide early warning indicators of exploitation attempts in environments where immediate patching is delayed.
This incident underscores the importance of maintaining up-to-date software versions to mitigate risks associated with complex web platform features that interact closely with system resources. The integration of industry-standard frameworks such as MITRE ATT&CK helps contextualize this vulnerability within broader threat landscapes, specifically under techniques related to initial access and execution via browser-based vectors. By understanding the mechanics of use-after-free vulnerabilities in modern browsers, security professionals can better anticipate attack patterns and implement more robust defense-in-depth strategies that account for both application-level flaws and systemic architectural weaknesses.