CVE-2026-113079 in Chrome
Summary
by MITRE • 10/21/2026
Use after free in SiteIsolation in Google Chrome prior to 156.0.8078.47 allowed a remote attacker to potentially 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 flaw within the SiteIsolation component of Google Chrome prior to version 156.0.8078.47 represents a critical memory safety issue that undermines the browser's core isolation mechanisms. Use-after-free errors occur 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 SiteIsolation, a security feature designed to enforce process boundaries between different origins or sites. By manipulating these boundaries improperly during memory deallocation and subsequent access, an attacker could trigger invalid memory operations within the context of a sandboxed renderer process. This type of vulnerability is classified under CWE-416, which addresses the dangerous use of pointers after their free time, highlighting the fundamental failure in managing object lifecycles correctly within complex software architectures like modern web browsers.
The operational impact of this vulnerability is significant because it allows for potential arbitrary code execution inside the sandboxed environment. Although Chrome employs a multi-process architecture where renderer processes are heavily restricted to limit the damage from exploits, bypassing these restrictions through memory corruption can lead to more severe consequences. A remote attacker could craft a malicious HTML page that triggers the use-after-free condition when rendered by the browser. Upon successful exploitation, this would allow the execution of arbitrary code within the context of the compromised renderer process. While the sandbox provides layers of defense such as restricted file system access and limited API availability, breaking out of or fully compromising a renderer can serve as a stepping stone for further attacks, including data exfiltration, session hijacking, or lateral movement if additional vulnerabilities are present in other browser components.
From an offensive security perspective, this vulnerability aligns with techniques described in the MITRE ATT&CK framework, specifically those related to client-side exploitation and sandbox escape attempts. The attack vector is classified as remote, meaning it can be triggered without any user interaction beyond visiting a maliciously crafted webpage or being redirected via phishing links. This ease of access increases the risk profile significantly, as automated drive-by download techniques could leverage this flaw for widespread compromise. The Chromium security severity rating of Medium reflects the balance between the complexity required to exploit the memory corruption and the potential impact on system integrity. It indicates that while exploitation is feasible, it may require specific conditions or additional vulnerabilities in certain contexts to achieve full control over the target machine.
Mitigation strategies primarily involve updating Google Chrome to version 156.0.8078.47 or later, where these memory management issues have been addressed by developers through rigorous code reviews and automated fuzzing tests that detect such lifecycle errors before release. For organizations managing large fleets of endpoints, deploying this update via centralized patch management systems is essential to close the exposure window. Additionally, users should maintain up-to-date antivirus and endpoint detection solutions that can monitor for suspicious memory access patterns indicative of exploitation attempts. Enabling Chrome’s built-in sandbox protections and keeping them enabled ensures that even if an exploit attempt occurs, the blast radius remains contained within isolated processes rather than affecting the host operating system directly. Regular security awareness training also helps reduce the likelihood of users interacting with malicious content that could trigger such vulnerabilities.