CVE-2026-106416 in Chrome
Summary
by MITRE • 10/07/2026
Code injection in Extensions in Google Chrome prior to 155.0.8059.39 allowed a remote attacker leveraging social engineering to spoof UI elements via a crafted Chrome extension. (Chromium security severity: Medium)
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Analysis
by VulDB Data Team • 10/07/2026
The vulnerability identified as code injection within the extensions architecture of Google Chrome, specifically affecting versions prior to 155.0.8059.39, represents a significant risk related to user interface spoofing and trust boundary violations. This flaw stems from an insufficient validation or sanitization mechanism when processing data passed between different components of the browser's extension system. In a typical Chrome environment, extensions operate within isolated contexts known as content scripts, background pages, and popup windows, each with specific permissions and access levels defined by manifest files. The vulnerability arises when these boundaries are not strictly enforced during the rendering or manipulation of user interface elements, allowing maliciously crafted code to inject itself into legitimate UI components. This technical flaw enables a remote attacker to manipulate how information is presented to the end-user without altering the underlying application logic in a detectable manner.
The operational impact of this vulnerability centers on social engineering attacks facilitated by UI spoofing. By leveraging the ability to inject arbitrary HTML, CSS, or JavaScript into trusted interface elements, an attacker can create deceptive overlays that mimic legitimate browser dialogs, login prompts, or security warnings. For instance, an attacker could craft a malicious extension that displays a fake certificate error warning designed to trick users into entering credentials on a phishing site, or simulate a system update prompt to coerce the installation of additional malware. Because these spoofed elements appear within the trusted context of the Chrome browser window, they benefit from the inherent trust users place in the interface itself. This undermines the principle of least privilege and confuses the user regarding the true origin and intent of the interaction, leading to potential credential theft, session hijacking, or further compromise through malicious downloads initiated under false pretenses.
From a classification perspective, this vulnerability aligns with CWE-94, which describes Improper Control of Generation of Code (Code Injection), specifically where the injected code affects the presentation layer rather than just backend logic. It also maps to ATT&CK technique T1059, Command and Scripting Interpreter, as it involves executing arbitrary scripts within a trusted environment. Furthermore, the social engineering aspect relates to MITRE ATT&CK tactic TA0001, Initial Access, specifically through techniques like Spearphishing Attachment or Valid Accounts if combined with other exploits. The severity is rated as Medium by Chromium security standards because while it does not directly allow remote code execution on the host system in the traditional sense of breaking out of the sandbox, it effectively bypasses user awareness and consent mechanisms, which are critical layers of defense against phishing and social engineering campaigns.
Mitigation strategies for this vulnerability primarily involve updating to Google Chrome version 155.0.8059.39 or later, where the underlying code injection flaw has been patched through stricter validation of extension content scripts and improved isolation between UI components. Organizations should enforce policies that restrict the installation of extensions from unknown sources by utilizing enterprise management tools such as Chrome Enterprise Policy or Microsoft Intune to whitelist only approved extensions. Additionally, user education remains critical; administrators should train users to verify the publisher information displayed in extension details pages and to be skeptical of any dialog boxes requesting sensitive data, even if they appear within the browser window. Regular auditing of installed extensions can help identify potentially malicious add-ons that may have been introduced through social engineering prior to patching.