CVE-2026-7931 Overview
CVE-2026-7931 is a user interface (UI) spoofing vulnerability in Google Chrome on iOS prior to version 148.0.7778.96. The flaw stems from insufficient validation of untrusted input within the iOS-specific implementation of Chrome. A remote attacker can deliver a crafted HTML page that manipulates browser UI elements to mislead users about the origin or authenticity of displayed content. Chromium classifies the security severity as Medium. The weakness is tracked under CWE-20: Improper Input Validation and primarily enables phishing and social engineering attacks against mobile Chrome users.
Critical Impact
Attackers can craft malicious HTML pages that spoof Chrome iOS browser UI, enabling convincing phishing campaigns that trick users into disclosing credentials or sensitive data.
Affected Products
- Google Chrome on iOS prior to 148.0.7778.96
- Apple iPhone OS (iOS) running vulnerable Chrome builds
- Chromium-based iOS browser distributions sharing the affected codebase
Discovery Timeline
- 2026-05-06 - CVE-2026-7931 published to NVD
- 2026-05-06 - Last updated in NVD database
Technical Details for CVE-2026-7931
Vulnerability Analysis
The vulnerability resides in the Chrome iOS browser's handling of attacker-controlled HTML content. Chrome on iOS does not adequately validate certain inputs before rendering them in or near trusted UI surfaces. As a result, a crafted page can produce visual elements that imitate authentic browser chrome, address bar content, or security indicators. The user is required to interact with the malicious page, but no privileges or authentication are needed by the attacker. Confidentiality and availability impacts are limited, while integrity is not directly affected at the system level. The practical risk centers on credential theft and social engineering rather than code execution or data corruption.
Root Cause
The root cause is improper input validation [CWE-20] in iOS-specific browser code paths that process untrusted HTML. Boundary conditions between page-rendered content and native iOS browser UI are not strictly enforced, allowing attacker-supplied content to influence what users perceive as authoritative browser indicators.
Attack Vector
Exploitation requires a victim to visit or be redirected to an attacker-controlled webpage in Chrome on iOS. The attacker crafts HTML that exploits the input validation gap to overlay, mimic, or manipulate UI elements. Typical scenarios include spoofed login prompts, fake URL displays, and counterfeit security warnings used to harvest credentials or push malicious downloads. Delivery vectors include phishing emails, malvertising, and compromised websites.
No verified public exploit code is available. See the Chromium Issue Tracker entry for technical context once details are released.
Detection Methods for CVE-2026-7931
Indicators of Compromise
- User reports of unusual login prompts, mismatched URLs, or unexpected security warnings inside Chrome on iOS.
- Web traffic to recently registered domains hosting HTML that overlays or mimics mobile browser UI elements.
- Credential submissions from mobile devices to domains that do not match the legitimate service being impersonated.
Detection Strategies
- Inventory mobile endpoints and identify Chrome iOS installations running versions earlier than 148.0.7778.96.
- Inspect proxy and DNS logs for connections to phishing infrastructure delivering crafted HTML targeting mobile browsers.
- Correlate identity provider logs for authentication anomalies originating from iOS devices following web browsing sessions.
Monitoring Recommendations
- Monitor mobile device management (MDM) telemetry for Chrome iOS version compliance and patch adoption rates.
- Alert on user-reported phishing attempts referencing Chrome browser prompts or iOS-specific UI artifacts.
- Track outbound traffic from corporate iOS devices to known phishing categories and newly observed domains.
How to Mitigate CVE-2026-7931
Immediate Actions Required
- Update Google Chrome on iOS to version 148.0.7778.96 or later through the Apple App Store on all managed devices.
- Push a forced update policy through MDM to ensure rapid remediation across the mobile fleet.
- Notify users about the spoofing risk and reinforce verification of URLs and login prompts on mobile devices.
Patch Information
Google has released a fixed version of Chrome for iOS that addresses CVE-2026-7931. Refer to the Google Chrome Update Announcement for release details. Users should install Chrome 148.0.7778.96 or later from the App Store. No vendor-supplied configuration changes are required beyond applying the update.
Workarounds
- Restrict use of Chrome on iOS until the patched version is deployed, directing users to a fully patched alternative browser if necessary.
- Enable enterprise phishing protection at the email gateway and DNS layer to reduce delivery of crafted HTML pages.
- Train users to validate authentication prompts by inspecting URLs and avoiding credential entry from links opened on mobile devices.
# Example MDM compliance check for Chrome iOS version
# Pseudocode for an MDM policy condition
require app com.google.chrome.ios version >= 148.0.7778.96
action if non_compliant: prompt_update, restrict_corporate_data
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
