CVE-2026-121030 in Chrome
Summary
by MITRE • 11/03/2026
Incorrect authorization in DevTools 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: Medium)
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Analysis
by VulDB Data Team • 11/04/2026
The vulnerability identified as an incorrect authorization flaw within Google Chrome's DevTools component represents a significant breach in the browser's isolation mechanisms, specifically affecting versions prior to 157.0.8103.38. This issue stems from a failure in access control logic that governs how developer tools interact with web content and internal browser processes. While DevTools are primarily intended for debugging and development purposes, they possess elevated privileges compared to standard webpage execution contexts. The flaw allows these privileged interfaces to be accessed or manipulated by external entities under conditions where such access should strictly be denied or heavily restricted based on the origin of the request. This misconfiguration creates a pathway through which an attacker can bypass expected security boundaries, leveraging the trust that Chrome places in its own developer utilities to escalate privileges beyond what is permitted for standard web content.
The operational impact of this vulnerability centers on the potential for arbitrary code execution outside the browser's sandbox environment. By crafting a malicious HTML page and employing social engineering techniques to trick a user into opening it with DevTools enabled or accessible, an attacker can exploit the authorization gap. Once triggered, the crafted payload interacts with the vulnerable components in a manner that circumvents the standard security checks designed to contain code execution within isolated contexts. This allows the execution of arbitrary commands on the underlying operating system, effectively breaking out of the sandbox. Such an escape is particularly dangerous because it grants the attacker full control over the victim's machine capabilities associated with the browser process, potentially leading to data exfiltration, installation of persistent malware, or further lateral movement within a network if the compromised device is part of a larger infrastructure.
From a classification perspective, this vulnerability aligns closely with CWE-269, which denotes Improper Privilege Management, as it involves an actor obtaining privileges that they are not entitled to hold. Furthermore, the exploitation technique maps directly to MITRE ATT&CK techniques related to privilege escalation and sandbox escape, specifically those involving client-side attacks where social engineering is used to lower user defenses before executing technical exploits. The reliance on social engineering highlights that while the technical flaw provides the mechanism for compromise, human interaction remains a critical vector in the attack chain. This underscores the importance of not only patching software vulnerabilities but also educating users about the risks associated with interacting with untrusted content, especially when developer tools are involved or visible during browsing sessions.
Mitigation strategies primarily involve updating Google Chrome to version 157.0.8103.38 or later, where these authorization checks have been corrected and hardened against such bypass attempts. For organizations unable to patch immediately due to compatibility concerns, implementing strict content security policies can help restrict the execution of certain scripts that might attempt to interact with DevTools interfaces in unauthorized ways. Additionally, disabling developer tools for standard user profiles through group policy or enterprise management configurations can reduce the attack surface by removing the privileged interface entirely from everyday browsing contexts. Regular audits of browser extensions and plugins are also recommended, as some may inadvertently expose similar vulnerabilities if they rely on internal Chrome APIs without proper validation. Continuous monitoring for anomalous behavior in system logs related to chrome.exe processes can aid in detecting potential exploitation attempts in real-time before significant damage occurs.