CVE-2026-87626 in Chrome
Summary
by MITRE • 09/09/2026
Incorrect authorization in DeviceBoundSessionCredentials in Google Chrome prior to 153.0.8010.36 allowed a remote attacker to bypass web origin policy via crafted network traffic. (Chromium security severity: Medium)
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Analysis
by VulDB Data Team • 09/09/2026
The vulnerability identified as an incorrect authorization flaw within the DeviceBoundSessionCredentials component of Google Chrome prior to version 153.0.8010.36 represents a significant deviation from expected browser security boundaries. This issue stems from a logic error in how the browser validates and enforces origin policies for credentials that are bound to specific devices or hardware identifiers. In modern web architectures, browsers rely on strict same-origin policies to isolate content from different sources, preventing malicious scripts loaded from one domain from accessing sensitive data associated with another domain. The flaw allows an attacker who can craft specific network traffic to manipulate the credential binding process, effectively tricking the browser into treating a request originating from a hostile or untrusted context as if it were authorized by the legitimate origin. This bypass is particularly dangerous because DeviceBoundSessionCredentials are often used for high-security authentication flows where trust in the device identity is paramount, making their compromise more severe than standard session cookie leaks.
From a technical perspective, this vulnerability falls under the category of authorization failures where access control checks are not properly enforced against user-controlled input or network state. Specifically, it aligns with CWE-284 Improper Access Control and CWE-913 Improvement of Centralized Enforcement of Privileges. The attacker exploits the gap between the credential generation phase and its subsequent validation during network requests. By crafting malicious network traffic that mimics legitimate device-bound sessions but lacks proper origin verification or contains manipulated headers, the adversary can inject unauthorized commands or extract sensitive data from protected web applications. This mechanism bypasses the browser's built-in protections designed to prevent cross-site request forgery and cross-origin data theft, effectively neutralizing a core defense layer of the Chromium engine.
The operational impact of this vulnerability is substantial for users relying on Chrome for secure transactions, corporate logins, or access to sensitive web applications that utilize device-bound authentication mechanisms. An attacker could potentially perform actions on behalf of the victim without their consent, such as transferring funds, changing account settings, or exfiltrating personal information stored in protected cookies or local storage associated with those credentials. Furthermore, because this is a remote code execution vector via network traffic manipulation, it does not require physical access to the device nor social engineering tactics beyond hosting malicious content that triggers the crafted request. This makes it scalable and difficult for end-users to detect without updated browser security features in place.
Mitigation strategies primarily involve immediate patching of the Google Chrome installation to version 153.0.8010.36 or later, which addresses the logic error within the DeviceBoundSessionCredentials handling routine. For organizations managing fleets of devices, deploying this update via centralized management tools is critical to reduce exposure windows. Additionally, web application developers should implement additional server-side validation for all requests involving device-bound credentials, ensuring that origin headers are strictly verified against a whitelist and that anti-CSRF tokens are utilized where applicable. Monitoring network logs for anomalous patterns in credential usage can also aid in early detection of exploitation attempts while the patch is being deployed across infrastructure.
This vulnerability maps to several techniques within the MITRE ATT&CK framework, particularly T1078 Valid Accounts and T1534 Internal Spearphishing if used in conjunction with social engineering, though its primary classification relates to privilege escalation through authorization bypasses. It underscores the importance of rigorous code review for security-critical components like session management systems within browsers. Security teams should prioritize this update due to the medium severity rating assigned by Chromium and the high potential impact on data confidentiality and integrity. Regular vulnerability scanning and penetration testing that includes browser-based attack vectors can help identify similar implementation flaws in custom web applications before they are exploited in the wild.