CVE-2026-5885: Google Chrome Information Disclosure Flaw

CVE-2026-5885 Overview

CVE-2026-5885 is an improper input validation vulnerability in the WebML implementation within Google Chrome on Windows. This security flaw allows a remote attacker to potentially obtain sensitive information from process memory by luring a victim to a specially crafted HTML page. The vulnerability exists in versions prior to 147.0.7727.55 and stems from insufficient validation of untrusted input within the WebML component.

Critical Impact

Remote attackers can exploit this vulnerability to extract sensitive information from browser process memory through malicious web pages, potentially exposing credentials, session tokens, or other confidential data processed by Chrome.

Affected Products

• Google Chrome on Windows prior to version 147.0.7727.55
• Chromium-based browsers on Windows using vulnerable WebML implementations

Discovery Timeline

• April 8, 2026 - CVE CVE-2026-5885 published to NVD
• April 8, 2026 - Last updated in NVD database

Technical Details for CVE-2026-5885

Vulnerability Analysis

This vulnerability is classified under CWE-20 (Improper Input Validation), indicating that the WebML component fails to properly validate input data before processing it. WebML is a web standard API that enables machine learning capabilities directly in the browser, allowing web applications to run neural network inference using hardware acceleration.

The insufficient validation occurs when the WebML implementation processes untrusted input from web content. Without proper boundary checking and input sanitization, attackers can craft malicious HTML pages that trigger out-of-bounds memory reads or other memory disclosure conditions within the Chrome renderer process.

Root Cause

The root cause of CVE-2026-5885 lies in missing or inadequate input validation routines within Chrome's WebML implementation. When processing neural network models or inference operations submitted through web content, the WebML component fails to verify that input parameters conform to expected constraints. This allows attackers to supply malformed or unexpected values that cause the component to read beyond allocated memory boundaries.

Attack Vector

The attack vector for this vulnerability is network-based, requiring user interaction. An attacker must convince a victim to visit a malicious web page containing specially crafted HTML and JavaScript code that leverages the WebML API. When the victim's browser renders the malicious page, the WebML component processes the attacker-controlled input, triggering the memory information disclosure.

The attack flow typically involves:

1. Attacker creates a malicious web page with crafted WebML API calls
2. Victim visits the attacker-controlled or compromised website
3. Chrome's WebML component processes the malicious input without proper validation
4. Sensitive data from process memory is exposed and can be exfiltrated to the attacker

The vulnerability mechanism exploits the WebML neural network inference pipeline. When malformed tensor dimensions or model parameters are supplied, the WebML implementation may read memory beyond the intended buffer boundaries, exposing potentially sensitive process memory contents. For technical implementation details, refer to the Chromium Issue Tracker Entry.

Detection Methods for CVE-2026-5885

Indicators of Compromise

• Unusual WebML API calls with abnormal tensor dimensions or model parameters in browser logs
• Network traffic containing HTML pages with suspicious WebML JavaScript code patterns
• Browser crash reports or memory access violations originating from WebML components
• Outbound data exfiltration following visits to untrusted websites

Detection Strategies

• Monitor browser extension and security tool logs for WebML-related anomalies
• Implement network traffic analysis to detect potential exploit delivery via malicious HTML pages
• Deploy endpoint detection solutions capable of identifying suspicious browser memory access patterns
• Review web proxy logs for access to known malicious domains hosting exploit code

Monitoring Recommendations

• Enable Chrome's built-in Safe Browsing and security features to detect known malicious sites
• Monitor for Chrome renderer process anomalies that may indicate exploitation attempts
• Implement browser telemetry collection to identify unusual WebML API usage patterns
• Track browser version compliance across the organization to identify vulnerable installations

How to Mitigate CVE-2026-5885

Immediate Actions Required

• Update Google Chrome to version 147.0.7727.55 or later immediately
• Enable automatic Chrome updates to ensure timely security patch deployment
• Review and restrict access to untrusted websites through web filtering solutions
• Consider temporarily disabling WebML features if immediate patching is not possible

Patch Information

Google has addressed this vulnerability in Chrome version 147.0.7727.55. Organizations should prioritize updating all Chrome installations to this version or later. The fix implements proper input validation for the WebML component, preventing attackers from triggering memory information disclosure through malformed input.

For detailed patch information, refer to the Google Chrome Update Announcement.

Workarounds

• Implement strict web content policies to block access to untrusted or suspicious websites
• Use browser isolation technologies to contain potential exploitation attempts
• Deploy network-level protections to filter malicious HTML content before it reaches end users
• Consider using enterprise browser configurations that restrict potentially dangerous web APIs

# Configuration example - Verify Chrome version
# Run this command to check your current Chrome version
google-chrome --version

# On Windows, check via PowerShell
(Get-Item "C:\Program Files\Google\Chrome\Application\chrome.exe").VersionInfo.ProductVersion

# Ensure version is 147.0.7727.55 or higher to be protected against CVE-2026-5885