CVE-2026-113042 in Chrome
Summary
by MITRE • 10/21/2026
Use after free in Extensions 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 Extensions component of Google Chrome prior to version 156.0.8078.47 represents a critical memory management flaw that undermines the browser's sandboxing mechanisms. This specific class 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 the context of web browsers, such vulnerabilities are particularly dangerous because they reside within components designed to handle untrusted content from remote websites. The presence of this flaw in the Extensions subsystem indicates that an attacker could manipulate how extension-related memory is allocated and deallocated during the processing of a crafted HTML page, thereby gaining unauthorized access to system resources or executing arbitrary code within the browser's process space.
From a technical perspective, use-after-free vulnerabilities typically arise when reference counting mechanisms fail to properly track object lifecycles or when pointers are not nullified after memory release. In Google Chrome’s architecture, extensions operate with elevated privileges compared to standard web pages but remain confined within a sandboxed environment to limit the impact of potential exploits. However, if an attacker can trigger a use-after-free condition in this layer, they may be able to achieve arbitrary code execution by controlling the contents of the freed memory region. By carefully crafting HTML content that forces specific allocation and deallocation patterns, an adversary could overwrite critical data structures or hijack control flow instructions, effectively bypassing the sandbox protections intended to isolate malicious web content from the underlying operating system.
The operational impact of this vulnerability is severe, as it allows for remote code execution without user interaction beyond visiting a compromised website. An attacker hosting a specially crafted HTML page can exploit this flaw when a victim with an affected version of Chrome visits the site and has relevant extensions installed or active. Successful exploitation could lead to full compromise of the browser session, including access to cookies, saved passwords, browsing history, and potentially sensitive data stored by web applications. Furthermore, depending on the specific extension permissions granted, the attacker might escalate privileges further within the user’s environment, leading to broader system compromise if additional vulnerabilities are chained with this initial entry point.
This incident aligns with Common Weakness Enumeration (CWE) identifier CWE-416, which describes use after free errors as a significant category of memory safety issues prevalent in C and C++ based software like Chromium. Additionally, the exploitation technique falls under MITRE ATT&CK tactic T1059, specifically Command and Scripting Interpreter subtechniques, where attackers execute arbitrary commands on compromised systems. The severity rating of Medium by the Chromium security team reflects the complexity required to reliably exploit this flaw in a real-world scenario, considering modern browser mitigations such as heap randomization and sandbox isolation, yet it remains a high-risk issue due to its potential for remote code execution.
To mitigate the risks associated with this vulnerability, users must immediately update Google Chrome to version 156.0.8078.47 or later, where these memory management issues have been addressed through rigorous patching and improved lifecycle tracking within the Extensions component. Security administrators should enforce automatic updates for all client machines to ensure timely protection against newly disclosed vulnerabilities. Additionally, organizations can reduce their attack surface by auditing installed browser extensions and removing any that are unnecessary or untrusted, thereby limiting the potential impact of a successful exploit. Implementing strict content security policies and monitoring for anomalous network traffic originating from browser processes can also provide early detection indicators for exploitation attempts targeting this class of memory corruption flaws.