CVE-2026-87532 in Chrome
Summary
by MITRE • 09/09/2026
Improper state validation in Safebrowsing in Google Chrome prior to 153.0.8010.36 allowed a remote attacker 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 an improper state validation flaw within the Safebrowsing component of Google Chrome prior to version 153.0.8010.36 represents a significant deviation from expected security boundaries in web browsing contexts. This issue stems from inadequate checks performed by the browser when processing navigation requests and validating the integrity of user states during interactions with remote resources. Specifically, the Safebrowsing subsystem, which is responsible for protecting users against malicious websites and downloads, failed to properly validate certain internal state transitions or permissions associated with specific HTML elements or scripts embedded in a crafted webpage. This oversight allowed an attacker to manipulate the browser's perception of trust levels, effectively tricking the security mechanisms into treating untrusted content as safe or permitted under current user privileges.
From a technical perspective, this flaw falls squarely within the domain of CWE-20 Improper Input Validation and often intersects with CWE-436 Interpretation Error when the state validation logic misinterprets the context of incoming data. The attacker leverages a specially constructed HTML page that exploits these gaps in state management to bypass system access restrictions. By carefully crafting the payload, the adversary can induce conditions where the browser fails to enforce critical security policies such as same-origin policy constraints or sandboxing rules intended for untrusted content. This misalignment between the actual execution context and the validated permission state enables actions that should have been blocked by default browser safeguards.
The operational impact of this vulnerability is categorized with a medium severity rating in Chromium, reflecting its potential to facilitate further exploitation chains rather than causing immediate catastrophic system compromise on its own. A remote attacker can use this flaw to bypass access restrictions, potentially leading to unauthorized data exfiltration, session hijacking, or the execution of arbitrary code within the browser's process space if combined with other vulnerabilities. The ability to circumvent these protections undermines the fundamental trust model of web browsers, where users rely on the isolation between different origins and the integrity of security features like Safebrowsing to prevent malicious activities.
In terms of threat modeling, this type of vulnerability is frequently associated with ATT&CK technique T1059 Command and Scripting Interpreter if it leads to script execution, or more broadly with initial access vectors that rely on social engineering via phishing pages designed to exploit browser flaws. The exploitation requires the victim to visit a maliciously crafted webpage, making user interaction a prerequisite for successful attack realization. However, once triggered, the bypass of system access restrictions can serve as a stepping stone for more advanced persistent threats or data theft operations targeting sensitive information stored within the browser profile.
Mitigation strategies primarily involve updating Google Chrome to version 153.0.8010.36 or later, where these state validation checks have been hardened and corrected by the development team. Organizations should ensure that endpoint protection solutions are configured to detect attempts to exploit known browser vulnerabilities through network traffic analysis or behavioral monitoring. Additionally, users can reduce risk exposure by disabling JavaScript on untrusted sites via browser settings or using extensions that enforce strict content security policies. Regular patch management cycles remain the most effective defense against such state-based logic errors in widely deployed software components like web browsers.