CVE-2026-79088 in Chrome
Summary
by MITRE • 08/26/2026
Incorrect authorization in FileSystem in Google Chrome prior to 152.0.7977.65 allowed a remote attacker leveraging social engineering to bypass system access restrictions via a crafted HTML page. (Chromium security severity: Medium)
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Analysis
by VulDB Data Team • 08/26/2026
The vulnerability identified as an incorrect authorization issue within the FileSystem API of Google Chrome prior to version 152.0.7977.65 represents a significant breach in web application sandboxing principles. This flaw allows remote attackers, who typically rely on social engineering tactics such as phishing or malicious website hosting, to bypass system access restrictions that are normally enforced by the browser's security model. The FileSystem API is designed to provide web applications with controlled access to local file systems, enabling features like saving documents directly from a browser-based editor. However, due to improper authorization checks within this component, an attacker can craft a malicious HTML page that exploits these logic errors to gain unauthorized read or write permissions to files and directories on the victim's machine that should remain inaccessible to untrusted web content.
From a technical perspective, the core of this vulnerability lies in the failure of the browser to correctly validate whether the requesting origin has been granted explicit permission by the user for specific file system paths. In a secure implementation, access requests must be strictly scoped and verified against the permissions model established during user interaction or through persistent storage grants. The flaw suggests that the authorization logic did not adequately isolate the request context from the broader operating system privileges, allowing the crafted page to traverse directory boundaries or access sensitive locations outside its intended sandbox. This type of error is characteristic of logical flaws where input validation and permission checks are either missing, incorrectly implemented, or bypassed through specific sequence attacks against the API's state management mechanisms.
The operational impact of this vulnerability is substantial for end-users who rely on Chrome as their primary browsing environment. An attacker leveraging social engineering can trick a user into visiting a malicious site that automatically triggers the exploit without further interaction once permissions are granted or if the browser defaults allow broader access. The consequence includes potential data exfiltration, where sensitive personal documents, configuration files, or credentials stored locally could be read and transmitted to remote servers controlled by the attacker. Furthermore, write capabilities could lead to file tampering, malware persistence through dropped executables in accessible directories, or corruption of critical system files depending on the level of access achieved. This undermines the fundamental trust users place in their web browsers as safe environments for handling sensitive information.
This vulnerability aligns with Common Weakness Enumeration (CWE) category CWE-269, which describes Improper Privilege Management, specifically where an actor obtains privileges it should not have due to a failure in authorization logic. It also maps closely to MITRE ATT&CK technique T1059, Command and Scripting Interpreter, as the exploitation often involves executing scripts or commands via file system interactions, and potentially T1560, Archive Collected Data, if the goal is data staging before exfiltration. The social engineering aspect highlights the importance of user awareness alongside technical controls, as initial access is frequently gained through deception rather than pure code execution flaws in this context.
Mitigation strategies primarily involve updating to Google Chrome version 152.0.7977.65 or later, where these authorization checks have been corrected and hardened against such bypass attempts. For organizations managing large fleets of devices, deploying automated patch management solutions ensures that updates are applied promptly to close this window of exposure. Additionally, users should be educated on the risks associated with granting file system permissions to unfamiliar websites and advised to review permission settings regularly within browser security menus. Implementing strict Content Security Policies (CSP) can also help mitigate some downstream effects by restricting how scripts interact with local resources, although relying solely on CSP is insufficient given that this flaw exists at the API authorization level rather than in script execution logic alone.