CVE-2026-113037 in Chrome
Summary
by MITRE • 10/21/2026
Use after free in WebSockets 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)
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Analysis
by VulDB Data Team • 10/21/2026
The vulnerability identified as a use-after-free condition within the WebSockets implementation of Google Chrome prior to version 156.0.8078.47 represents a critical memory safety flaw that undermines the browser's sandboxing mechanisms. This type of error occurs when a program continues to use a pointer after the memory it points to has been freed, leading to undefined behavior that can be exploited by malicious actors. In this specific instance, the flaw resides in how Chrome manages WebSocket connections and their associated resources during lifecycle transitions or state changes. When an attacker crafts a specialized HTML page containing JavaScript code designed to trigger these race conditions or improper cleanup routines, they can manipulate the internal memory structures of the browser process. The exploitation vector relies on precise timing and object allocation strategies that allow the attacker to reallocate the freed memory with controlled data before it is accessed again by the WebSocket engine.
From a technical perspective, this vulnerability falls under the Common Weakness Enumeration category CWE-416, which defines use after free as a situation where an application uses a pointer referencing deallocated memory. The operational impact of such a flaw in a web browser context is severe because browsers rely heavily on sandboxing to isolate untrusted content from the host operating system and user data. By exploiting this memory corruption issue, a remote attacker can achieve arbitrary code execution within the restricted environment of the Chrome renderer process. While the Chromium security severity was rated as Medium, indicating that it might require specific conditions or limited impact in some scenarios, successful exploitation allows for full control over the browser's internal state. This level of access is often sufficient to bypass sandbox protections and escalate privileges to execute code on the underlying operating system, potentially leading to data exfiltration, installation of malware, or complete compromise of the victim's device.
The attack scenario typically involves a user visiting a malicious website that hosts the crafted HTML page. The JavaScript embedded in this page interacts with WebSocket APIs to create connections and trigger specific events that expose the timing window for the use-after-free condition. Once triggered, the attacker gains the ability to write arbitrary data into memory locations previously freed by the browser's garbage collector or cleanup routines. This corruption can overwrite function pointers or object vtables, redirecting execution flow to shellcode injected by the attacker. The presence of modern exploit mitigations such as Address Space Layout Randomization and Data Execution Prevention may complicate exploitation but does not eliminate the risk entirely, especially if additional vulnerabilities are chained together to bypass these defenses.
To mitigate this vulnerability, organizations and individual users must ensure that Google Chrome is updated to version 156.0.8078.47 or later immediately upon availability. This update contains patches that correct the memory management logic within the WebSocket implementation, ensuring that pointers are properly nullified after deallocation and preventing access to freed memory regions. Additionally, security teams should enforce strict content security policies and consider deploying browser isolation technologies such as Microsoft Edge IE Mode or third-party sandboxing solutions like Sandboxie to limit the blast radius of any potential future exploits. Monitoring for anomalous network activity related to WebSocket connections from untrusted sources can also provide early warning indicators of exploitation attempts in progress.
In terms of threat intelligence frameworks, this vulnerability aligns with ATT&CK technique T1203, which covers Exploitation for Client Execution, where attackers leverage vulnerabilities in client software like web browsers to execute malicious code on the target system. The use-after-free mechanism is a classic precursor to more advanced exploitation techniques and highlights the importance of rigorous memory safety practices in browser development. Developers should prioritize static analysis tools and fuzzing during the coding phase to detect such issues before they reach production builds. For security analysts, recognizing patterns associated with WebSocket manipulation and unusual memory access behaviors can aid in detecting attempts to exploit similar vulnerabilities in other applications that rely on similar networking stacks or JavaScript engines.