CVE-2026-121060 in Chrome
Summary
by MITRE • 11/03/2026
Incorrect authorization in FileSystem in Google Chrome prior to 157.0.8103.38 allowed a remote attacker leveraging social engineering to potentially 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 an incorrect authorization flaw within the FileSystem API of Google Chrome prior to version 157.0.8103.38 represents a significant breach in browser-based access control mechanisms. This specific weakness allows for unauthorized interactions with file system resources that are typically restricted by security policies designed to isolate web content from local operating system files. The core technical flaw lies in the improper validation of permissions when handling requests related to directory or file operations, which fails to strictly enforce the sandbox boundaries established by the browser engine. Consequently, a remote attacker can exploit this misconfiguration through social engineering tactics, such as luring a user into visiting a maliciously crafted HTML page that triggers these flawed authorization checks.
From an operational perspective, the impact of this vulnerability is severe because it facilitates arbitrary code execution outside the protective sandbox environment. Modern browsers rely heavily on process isolation and sandboxing to contain potential exploits within limited privilege contexts, thereby preventing malware from gaining full control over the host system. By bypassing or circumventing these restrictions via the FileSystem API, an attacker can potentially write executable files to disk, modify critical system configurations, or establish persistence mechanisms that operate with higher privileges than intended by the browser's security model. This effectively transforms a web-based attack vector into a direct threat against endpoint integrity and confidentiality.
The exploitation of this flaw aligns closely with CWE-269, which describes Improper Privilege Management, specifically regarding the failure to enforce required permissions for specific actions within an application context. Furthermore, in terms of offensive security frameworks such as MITRE ATT&CK, this vulnerability supports techniques associated with Initial Access through social engineering and subsequent Execution via local file creation or modification. The attacker leverages user interaction to bypass automated defenses, highlighting the critical intersection between technical vulnerabilities and human factors in cybersecurity defense strategies.
Mitigation for this issue primarily involves immediate software updates to ensure that all instances of Google Chrome are upgraded to version 157.0.8103.38 or later, where these authorization checks have been corrected. Organizations should also enforce strict content security policies and consider deploying browser isolation solutions to further limit the potential impact of any future zero-day vulnerabilities in web rendering engines. Additionally, user education regarding social engineering tactics remains essential, as this vulnerability relies on deceptive practices to initiate the exploitation chain. Regular patch management cycles and monitoring for anomalous file system activity can provide additional layers of defense against such exploits.