CVE-2026-106291 in Chrome
Summary
by MITRE • 10/06/2026
Use after free in GarbageCollection in Google Chrome prior to 155.0.8059.39 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 • 10/07/2026
The vulnerability identified as a use-after-free error within the GarbageCollection component of Google Chrome prior to version 155.0.8059.39 represents a critical memory management flaw that undermines the browser's sandboxing mechanisms. This specific class of defect occurs when the garbage collection subsystem fails to properly manage object lifecycles, allowing JavaScript code or other script engines to access and manipulate memory regions that have already been deallocated by the system. In modern web browsers like Chrome, this is particularly dangerous because it bypasses the strict isolation boundaries designed to prevent malicious content from affecting the host operating system or accessing sensitive user data. The Chromium security team has classified this issue with a medium severity rating, reflecting its potential for exploitation under specific conditions while acknowledging that successful attacks may require additional factors such as social engineering or complex exploit chains.
From a technical perspective, use-after-free vulnerabilities arise when an application continues to use a pointer after the memory it points to has been freed. In the context of Chrome's garbage collection process, this typically involves JavaScript objects being marked for deletion but not immediately reclaimed due to asynchronous processing delays or race conditions in reference counting mechanisms. An attacker can craft a malicious HTML page that triggers these timing windows by rapidly creating and destroying objects while simultaneously attempting to access them through carefully constructed script logic. This allows the attacker to achieve arbitrary read and write primitives within the browser's renderer process, which is essential for escalating privileges from the sandboxed environment to full system compromise. The exploitation of this flaw does not require physical access or prior authentication on the target machine, making it a remote code execution vector that can be delivered via standard web browsing activities such as visiting a compromised website or clicking a phishing link.
The operational impact of this vulnerability is significant for both individual users and enterprise environments relying on Chrome for secure internet access. Successful exploitation enables an attacker to execute arbitrary commands within the context of the browser process, potentially leading to data exfiltration, installation of persistent malware, or further lateral movement in networked environments where browsers are used as gateways. Although the sandbox provides a layer of defense by restricting what code can do once executed, memory corruption bugs like use-after-free often allow attackers to escape this confinement through techniques such as heap spraying andROP chains that overwrite function pointers or return addresses. This effectively neutralizes many of the security benefits provided by modern browser architectures, leaving systems vulnerable to comprehensive compromise without any user interaction beyond visiting a malicious site.
Mitigation strategies primarily involve updating Google Chrome to version 155.0.8059.39 or later, where these memory management issues have been addressed through improved reference tracking and stricter validation of object states during garbage collection cycles. Organizations should enforce automated update policies to ensure all endpoints are running the latest stable release, as patch availability is a critical factor in reducing exposure windows. Additionally, deploying browser isolation solutions or web content filtering can provide an additional layer of defense by preventing access to untrusted domains that might host exploit kits targeting this vulnerability. Security teams should also monitor for indicators of compromise associated with known exploitation techniques related to heap corruption and use-after-free scenarios, such as unusual memory allocation patterns or unexpected process behavior within the renderer processes.
This incident aligns with Common Weakness Enumeration identifier CWE-416, which describes use after free conditions that lead to undefined behavior and potential code execution. It also maps to MITRE ATT&CK techniques related to initial access via spearphishing links and defense evasion through memory manipulation, highlighting the importance of maintaining up-to-date software defenses against sophisticated web-based attacks. By addressing this vulnerability promptly, administrators can restore the integrity of their browsing environments and reduce the risk of successful remote code execution attempts targeting Chrome users globally.