CVE-2026-93386 in Chrome
Summary
by MITRE • 09/18/2026
UI misrepresentation in WebAppInstalls in Google Chrome prior to 153.0.8010.52 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 • 09/18/2026
The vulnerability identified as a user interface misrepresentation within the WebAppInstalls component of Google Chrome prior to version 153.0.8010.52 represents a significant trust boundary violation that exploits the browser's native application installation mechanisms. This flaw allows an attacker, through social engineering tactics and a specially crafted HTML page, to manipulate the visual presentation of user interface elements associated with web app installations. By spoofing these UI components, the vulnerability creates a deceptive environment where users may be misled into believing they are interacting with legitimate system prompts or trusted application installers rather than malicious code execution vectors. This type of attack falls squarely under the category of CWE-20: Improper Input Validation and more specifically aligns with CWE-831: Action Manipulation, as it involves tricking users into performing actions by presenting false information about those actions.
From a technical perspective, this vulnerability leverages the browser's permission model for Progressive Web Apps or native web app installations. When a user visits a webpage that triggers an installation prompt, Chrome typically displays a standardized dialog box to confirm the action and display details such as the application name and permissions requested. The flaw in versions prior to 153.0.8010.52 allows malicious actors to overlay or replace these standard dialogs with custom HTML elements that mimic the appearance of official browser prompts. This spoofing capability undermines the user's ability to distinguish between genuine system-level interactions and attacker-controlled content, effectively bypassing the cognitive safeguards users rely on to make informed security decisions. The severity is classified as Low by Chromium because it requires active user interaction and social engineering rather than exploiting a direct code execution flaw or memory corruption issue, yet its impact remains substantial due to the high trust placed in browser UI elements.
The operational impact of this vulnerability centers on increased susceptibility to phishing and credential harvesting attacks. An attacker can craft a scenario where a victim is directed to a malicious site that mimics a legitimate service's installation process. By spoofing the install prompt, the attacker can coerce users into granting excessive permissions or downloading malware under the guise of installing a trusted application. This erodes user trust in the browser interface and increases the success rate of social engineering campaigns. The attack vector is primarily remote via web delivery but relies heavily on human factors, making it difficult to mitigate solely through technical controls without also addressing user education and awareness training.
Mitigation strategies for this vulnerability involve immediate updates to Google Chrome version 153.0.8010.52 or later, which contains the necessary patches to correct the UI rendering logic in WebAppInstalls. Administrators should enforce automatic update policies across all endpoints to ensure users are protected against known interface spoofing techniques. Additionally, organizations can implement browser hardening configurations that restrict web app installation privileges for standard user accounts where such functionality is not strictly required. Security awareness programs should also be updated to educate employees about the importance of verifying the authenticity of installation prompts and checking URL consistency before interacting with any application installers. Monitoring network traffic for unusual patterns related to web app installations can provide an additional layer of detection, although this vulnerability primarily requires user vigilance as a primary defense mechanism alongside timely patching.