CVE-2026-11228: Chrome UI Spoofing Vulnerability via File Input Flaw

Technical summary

CVE-2026-11228 is a UI spoofing vulnerability stemming from inappropriate implementation in Chrome's File Input handler (CWE-451: User Interface (UI) Misrepresentation of Critical Information). The attack surface is network-based with no privilege escalation required. The vulnerability requires user interaction—specifically, the victim must perform deliberate UI gestures on the attacker's crafted HTML page. Once triggered, the attacker can overlay or misrepresent critical UI elements, potentially leading to credential harvesting, malware distribution confusion, or social engineering amplification. The CVSS 3.1 vector reflects low attack complexity, network accessibility, required user interaction, and integrity impact without confidentiality or availability loss.

Business impact

The primary risk is reputational and user trust erosion. Attackers could craft convincing phishing pages that appear to come from legitimate services or browser dialogs. Users may inadvertently grant permissions, download malware, or disclose sensitive information if they cannot visually distinguish legitimate from spoofed interface elements. For organizations, this creates support burden and potential credential compromise if users interact with attacker-controlled sites while authenticated to sensitive services. The medium CVSS score reflects that while real-world impact exists, exploitation requires user deception—not autonomous compromise.

Affected systems

Chrome on Windows, macOS, and Linux systems running versions prior to 149.0.7827.53 are vulnerable. The underlying Chrome security advisory identifies this as a Chromium Low severity issue, meaning the Chromium project assessed the practical exploitability and impact as constrained. Other Chromium-based browsers (Edge, Brave, Opera, etc.) may also be affected depending on their update cadence relative to Chromium 149.0.7827.53.

Exploitability

Exploitation is not wormable or autonomous. An attacker must author a crafted HTML page and convince or socially engineer a user to visit it and perform specific UI interactions. There is no exploit in the wild tracked in the Exploit Database, and this CVE has not been added to CISA's Known Exploited Vulnerabilities (KEV) catalog, suggesting exploitation remains theoretical or limited. The barrier to exploitation is moderate: technical skill is needed to craft the spoofing payload, but user tricking is the primary hurdle. Mass exploitation via drive-by downloads or zero-click vectors is not applicable here.

Remediation

Users and administrators should update Google Chrome to version 149.0.7827.53 or later. For managed deployments, Chrome update policies can be enforced via Group Policy (Windows), configuration profiles (macOS), or Linux package managers. The fix addresses the file input implementation defect, eliminating the vector for UI spoofing via this mechanism. No workarounds are available; patching is the only mitigation.

Patch guidance

Install Chrome version 149.0.7827.53 or any later release. Users can check their current version at chrome://version/ and enable automatic updates (default behavior). For enterprise Chrome deployments, verify update policies are active and apply patches within standard change windows. Consider communicating to end users that they should be skeptical of unexpected permission prompts or file dialogs and verify authenticity through independent means (e.g., checking official websites directly).

Detection guidance

Detection is challenging because the vulnerability manifests as social engineering. Monitor for unusual download or permission-grant events from suspicious domains, and correlate with user reports of confusing dialogs. Endpoint detection and response (EDR) tools can log Chrome version inventory to identify unpatched systems. Web application firewalls can flag known attacker IP ranges or malicious referrer patterns, but the attack surface is broad (any website can host the malicious page). User awareness training—teaching users to verify permission dialogs and not interact with unsolicited file-open requests—is the most practical detection complement.

Why prioritize this

While the CVSS score is 4.3 (Medium), this CVE should not delay other critical patching but does warrant timely remediation within 30–60 days. The lack of known active exploitation, medium severity rating from Chromium, and reliance on user interaction place it below high-risk vulnerabilities. However, the ubiquity of Chrome and the potential for social engineering campaigns targeting specific user groups (e.g., financial sector, government contractors) merit prompt patching. Prioritize systems used by high-value targets or high-risk users.

Risk score, explained

The CVSS 3.1 score of 4.3 reflects: (1) Network attack vector—easily reachable remotely, (2) Low attack complexity—no special conditions required, (3) No privilege requirement, (4) Required user interaction via specific gestures, and (5) Integrity impact only (UI spoofing, no data breach). Confidentiality and availability are unaffected. Chromium's Low severity assessment aligns with this: the attack requires social engineering and provides no direct path to code execution, lateral movement, or data exfiltration. Organizations with strong user security awareness may accept this risk longer than a critical zero-day.

Frequently asked questions