CVE-2026-121045 in Chrome
Summary
by MITRE • 11/03/2026
UI misrepresentation in Browser in Google Chrome on on Mac prior to 157.0.8103.38 allowed a remote attacker leveraging social engineering to spoof UI elements via a crafted HTML page. (Chromium security severity: Low)
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Analysis
by VulDB Data Team • 11/03/2026
The vulnerability identified as a user interface misrepresentation in Google Chrome for macOS, specifically affecting versions prior to 157.0.8103.38, represents a classic social engineering attack vector where the browser's rendering engine is manipulated to display deceptive visual cues. This flaw allows a remote attacker, through the delivery of a specially crafted HTML page, to spoof critical user interface elements such as address bars, certificate indicators, or navigation buttons. By altering the perceived context of the browsing session, the vulnerability undermines the trust model that users rely on when interacting with web content, effectively creating a discrepancy between what is displayed and the actual underlying state of the browser application.
From a technical perspective, this issue stems from how Chrome handles layout rendering and DOM manipulation in specific edge cases involving CSS styling or JavaScript-driven UI updates. The attacker leverages these mechanisms to overlay fake elements on top of legitimate ones or modify existing elements to mimic trusted system interfaces. This technique is often referred to as clickjacking or UI redressing, where the visual presentation is decoupled from the functional reality. For instance, an attacker might create a transparent iframe that covers a malicious button while displaying a benign-looking interface above it, tricking the user into performing unintended actions such as granting permissions, downloading malware, or entering credentials on a phishing site that appears to be legitimate due to spoofed address bar details.
The operational impact of this vulnerability is primarily tied to successful social engineering campaigns rather than direct code execution or data exfiltration through technical exploits alone. The severity is classified as low by the Chromium security team because it requires user interaction and does not bypass sandboxing mechanisms directly. However, in practice, such vulnerabilities are highly effective for phishing attacks where users may be tricked into believing they are on a secure HTTPS page when they are actually on an HTTP site or a malicious domain. This can lead to credential theft, unauthorized account access, or the installation of unwanted software if the user is persuaded by the spoofed interface to click through warnings or accept dangerous prompts that appear legitimate due to the UI manipulation.
Mitigation strategies for this vulnerability involve both immediate patching and long-term defensive practices. The primary remediation is upgrading Google Chrome on macOS to version 157.0.8103.38 or later, which includes patches addressing these rendering inconsistencies. Users should also enable safe browsing features that provide additional warnings when navigating to potentially harmful sites. From a security architecture standpoint, implementing Content Security Policy headers can help restrict how scripts interact with the UI, reducing the attack surface for such spoofing techniques. Additionally, user education remains critical; organizations and individuals must be trained to verify URL details manually rather than relying solely on visual cues provided by the browser interface, as these can be artificially constructed by malicious web pages.
This vulnerability aligns with CWE-201, which describes insertion of sensitive information into an external entity in a way that could be read or manipulated by unauthorized actors, specifically through UI deception. It also maps to MITRE ATT&CK technique T1498, Network Sniffing, and more accurately T1566 Phishing, particularly the sub-technique of Spearphishing Attachment or Link where social engineering is used to trick users into taking actions that compromise security. The exploitation relies heavily on human factors rather than software bugs in cryptographic protocols or memory management, highlighting the persistent challenge of defending against attacks that target user perception and trust within web browsers.