CVE-2026-121114 in Chrome
Summary
by MITRE • 11/03/2026
Use after free in TabStrip in Google Chrome prior to 157.0.8103.38 allowed a remote attacker to execute arbitrary code outside the sandbox via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 11/03/2026
The vulnerability identified as a use-after-free flaw within the TabStrip component of Google Chrome prior to version 157.0.8103.38 represents a critical memory management error that compromises the browser's integrity and security posture. This specific defect occurs when an object is accessed after its memory has been deallocated, 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 responsible for managing user interface elements like tabs, which are frequently manipulated during normal browsing activities and through automated scripts embedded in web pages.
From a technical perspective, the TabStrip is part of Chrome's Chromium engine that handles the visual representation and state management of open browser tabs. When an attacker crafts a malicious HTML page containing specific JavaScript or DOM manipulation techniques, they can trigger conditions where references to tab objects persist even after those objects have been freed from memory. This creates a dangling pointer scenario where subsequent operations on these stale references interact with potentially reused memory regions controlled by the attacker. The exploitation of this flaw allows for arbitrary code execution outside the browser's sandbox environment, effectively bypassing one of Chrome's primary defense mechanisms designed to isolate web content and prevent malicious scripts from accessing sensitive system resources or user data.
The operational impact of this vulnerability is severe due to its remote exploitability via a crafted HTML page. An attacker does not need physical access or prior authentication; simply convincing a victim to visit the malicious webpage is sufficient to initiate the attack chain. Once exploited, the ability to execute arbitrary code outside the sandbox means that an adversary could install malware, steal sensitive information such as cookies and session tokens, perform keylogging, or use the compromised machine as part of a botnet. The high severity rating assigned by Chromium security reflects the ease with which this vulnerability can be leveraged in real-world phishing campaigns and drive-by download attacks targeting users who may not have updated their browsers to the latest secure version.
This type of memory corruption flaw is commonly categorized under CWE-416, Use After Free, within the Common Weakness Enumeration framework. It aligns with ATT&CK technique T1203, Exploitation for Client Execution, where attackers leverage software vulnerabilities in client applications to gain initial access and establish a foothold on target systems. The exploitation path typically involves crafting payloads that manipulate object lifecycles during tab switching or closure events, ensuring the freed memory is reallocated with attacker-controlled data before it is accessed again by the browser's rendering engine.
Mitigation strategies primarily involve immediate patching to version 157.0.8103.38 or later, which includes fixes for the TabStrip component that properly manage object lifecycles and prevent access to deallocated memory. Organizations should enforce automated update policies across all endpoints running Chrome to ensure timely application of security patches. Additionally, deploying browser isolation technologies or content security policies can provide additional layers of defense by restricting script execution capabilities within untrusted contexts. Security teams should also monitor for indicators of compromise associated with drive-by download campaigns targeting this specific vulnerability and educate users on the risks of visiting unknown websites until all systems are fully patched.