CVE-2026-87513 in Chrome
Summary
by MITRE • 09/09/2026
Missing authorization in ControlledFrame in Google Chrome prior to 153.0.8010.36 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 • 09/09/2026
The vulnerability identified as missing authorization within the ControlledFrame component of Google Chrome prior to version 153.0.8010.36 represents a critical flaw in how browser contexts manage permissions and access controls for embedded content. This issue stems from an insufficient validation mechanism when handling frames that are designated under controlled execution environments, such as those used by extensions or specific web APIs designed to restrict interaction with the main page context. In standard web architecture, iframes serve as isolated containers for external content, but certain privileged contexts require strict enforcement of same-origin policies and explicit user consent mechanisms to prevent unauthorized data exfiltration or state manipulation. The absence of proper authorization checks in this specific component allows a remote attacker to circumvent these intended security boundaries without triggering the usual browser prompts that would alert the user to potential risks.
From a technical perspective, the flaw enables an adversary to leverage social engineering tactics by hosting a malicious HTML page on a compromised or attacker-controlled server. When a victim visits this crafted webpage, it attempts to interact with ControlledFrame elements in a manner that bypasses standard permission dialogs. By exploiting the lack of authorization verification, the script can execute actions within the frame context that should be restricted, such as accessing sensitive browser APIs, reading cookies from other origins if isolation is compromised, or manipulating DOM elements that are supposed to remain inaccessible. This type of vulnerability aligns closely with CWE-269, which describes Improper Privilege Management, specifically where a process does not properly enforce the separation between its own privileges and those granted by external entities. It also relates to CWE-749, Exposed Dangerous Method or Function, as the underlying mechanism allows access to internal browser functions that are intended for restricted use only under verified conditions.
The operational impact of this vulnerability is significant due to its reliance on social engineering rather than complex exploitation techniques. Because the attack vector involves a crafted HTML page, it can be delivered through phishing emails, malicious advertisements, or compromised websites without requiring any software exploits beyond the browser itself. Once triggered, an attacker could potentially gain unauthorized access to user data stored within the scope of the affected frame, manipulate session states, or perform actions on behalf of the authenticated user if they are logged into sensitive services that rely on these frames for functionality. This undermines the fundamental trust model of web browsers, where users expect that embedded content cannot arbitrarily interact with their active sessions without explicit consent. The severity is rated as medium by Chromium security standards because while it requires user interaction to initiate, the ease of deployment and potential for data theft make it a persistent threat in modern phishing campaigns.
To mitigate this risk, organizations and individual users must ensure that Google Chrome is updated to version 153.0.8010.36 or later, where these authorization checks have been reinforced. Beyond patching, security awareness training remains crucial for mitigating the social engineering aspect of this attack vector. Users should be educated to recognize suspicious URLs and avoid interacting with unexpected prompts or content from untrusted sources. Additionally, implementing strict Content Security Policy (CSP) headers on web applications can help restrict how frames are loaded and what scripts they are permitted to execute, adding an additional layer of defense against unauthorized frame interactions. Monitoring browser logs for unusual activity related to iframe creation and permission requests can also aid in detecting attempted exploitation attempts before significant damage occurs. This incident highlights the ongoing need for rigorous validation of privilege boundaries within complex software ecosystems like web browsers, ensuring that even minor oversights in authorization logic do not lead to substantial security breaches.