CVE-2026-11107: Google Chrome UI Spoofing Vulnerability – Patch Guide

Technical summary

CVE-2026-11107 is a Medium-severity UI spoofing vulnerability (CVSS 3.1 score: 4.3) in the Downloads implementation of Google Chrome. The flaw stems from inappropriate handling of HTML rendering in the download feature, allowing a network-based attacker to craft a page that mimics legitimate browser UI elements. The attack vector is network-accessible, requires no special privileges, and depends on user interaction (clicking through or viewing the malicious page). The vulnerability maps to CWE-451 (User Interface (UI) Misrepresentation of Critical Information), reflecting that the integrity of displayed information is compromised but not data confidentiality or system availability.

Business impact

UI spoofing vulnerabilities pose a moderate but real threat to user trust and organizational security posture. While the CVSS score of 4.3 reflects limited direct impact, such flaws can be leveraged as part of social engineering or phishing attacks to trick users into downloading malware, revealing credentials, or performing unintended actions. Organizations relying on Chrome for workforce browsing should prioritize user awareness, as attackers could craft convincing fake dialogs or warning messages that users might mistrust legitimate browser warnings in the future. The reputational and trust implications, particularly if users in your organization become victims of downstream attacks relying on this spoofing technique, should not be underestimated.

Affected systems

Google Chrome is the primary affected application. The vulnerability impacts Chrome installations across multiple operating systems: Windows, macOS, and Linux. Any organization running Chrome versions prior to 149.0.7827.53 is exposed. Desktop and laptop deployments are the primary concern, though Chrome's prevalence on corporate endpoints means wide-scale exposure is possible in many enterprises.

Exploitability

Exploitability is straightforward but requires social engineering. The attack is network-based with low complexity—no special browser configuration or user privilege is needed. However, the user must interact with the malicious page (visiting it, likely via phishing link or drive-by compromise of a trusted site). The spoofed UI element itself does not automatically execute code; success depends on convincing the user to take action based on the fake interface. Public exploit code is not widespread, and the vulnerability is not tracked in CISA's Known Exploited Vulnerabilities (KEV) catalog, indicating limited real-world exploitation to date. Nevertheless, the attack surface is broad given Chrome's ubiquity.

Remediation

Update Google Chrome to version 149.0.7827.53 or later. This patch corrects the implementation flaw in the Downloads feature and eliminates the ability to spoof UI elements through crafted HTML. Users on managed Chrome deployments should prioritize rollout of this update. Additionally, consider reinforcing user security awareness training around verifying browser UI authenticity and avoiding suspicious download prompts.

Patch guidance

Verify that your Chrome deployment is running version 149.0.7827.53 or later. For enterprise environments using Chrome Enterprise or managed Google Chrome, consult your organization's update policy and test the patch in a non-production environment before full rollout. Automatic updates are enabled by default in consumer Chrome; ensure that auto-update is not disabled in your environment. Check Chrome's Settings > About Chrome to view the current version and force an immediate update check if needed.

Detection guidance

Direct detection of exploitation attempts is challenging because the attack relies on rendering behavior rather than network-level indicators. However, monitor for user reports of unusual download dialogs or browser warnings that seem out of place. Endpoint detection and response (EDR) tools may flag suspicious HTML files or phishing emails that attempt to deliver the exploit page. Network monitoring for traffic to known malicious domains used in campaigns exploiting this flaw, once identified in threat intelligence feeds, is advisable. Encourage users to report suspicious browser behavior or download prompts to your security team.

Why prioritize this

This vulnerability merits prompt but not emergency patching. The CVSS score of 4.3 and lack of KEV inclusion indicate low active exploitation. However, the broad install base of Chrome and the social engineering angle mean that widespread exploitation could occur if attack campaigns leverage this flaw. Prioritize patching in your organization based on user-facing risk: browsers used by employees handling sensitive communications, financial data, or high-value targets should be updated first. For most organizations, standard patch cycles (within 1-2 weeks) are acceptable unless you observe threat intelligence suggesting active exploitation.

Risk score, explained

The CVSS 3.1 vector AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N yields a score of 4.3 (Medium severity). The Network attack vector and Low complexity reflect easy reach to vulnerable systems, but the requirement for User Interaction (UI:R) and lack of impact on Confidentiality or Availability limit the score. The Limited Integrity impact (I:L) reflects that the user's perception of legitimate UI is compromised, not that system or data integrity is directly violated. This score appropriately captures a flaw that is easy to trigger but dependent on social engineering success and limited in direct harm.

Frequently asked questions