CVE-2026-5915 Overview
CVE-2026-5915 is an input validation vulnerability affecting the WebML component in Google Chrome prior to version 147.0.7727.55. The flaw stems from insufficient validation of untrusted input, which allows a remote attacker to perform an out-of-bounds memory write via a crafted HTML page. This vulnerability poses significant risk as it can be exploited remotely through user interaction with malicious web content.
Critical Impact
Remote attackers can trigger out-of-bounds memory writes through maliciously crafted HTML pages, potentially leading to data corruption and application crashes without requiring any special privileges.
Affected Products
- Google Chrome versions prior to 147.0.7727.55
- Chromium-based browsers using affected WebML implementation
- Desktop platforms running vulnerable Chrome versions
Discovery Timeline
- 2026-04-08 - CVE-2026-5915 published to NVD
- 2026-04-09 - Last updated in NVD database
Technical Details for CVE-2026-5915
Vulnerability Analysis
This vulnerability is classified as CWE-20 (Improper Input Validation), affecting the WebML API implementation in Google Chrome. WebML is Chrome's Web Machine Learning API that enables machine learning inference directly in the browser. The flaw occurs when the WebML component fails to properly validate input data, allowing attackers to manipulate memory boundaries.
The vulnerability can be exploited over the network but requires user interaction—specifically, a user must visit a malicious webpage or load attacker-controlled HTML content. Successful exploitation does not require authentication or elevated privileges, making it accessible to any remote attacker who can deliver malicious content to potential victims.
Root Cause
The root cause lies in insufficient boundary checking within the WebML input processing routines. When handling untrusted input data for machine learning operations, the WebML component fails to adequately validate input parameters before performing memory operations. This lack of proper input sanitization allows attackers to supply specially crafted values that cause the application to write data outside of allocated memory boundaries.
Attack Vector
The attack is network-based and requires user interaction. An attacker constructs a malicious HTML page containing specially crafted WebML API calls designed to exploit the input validation weakness. When a victim visits the attacker-controlled page, the malformed input triggers an out-of-bounds memory write condition.
The attack flow typically involves:
- Attacker creates a webpage with malicious WebML API invocations
- Victim navigates to the attacker's page or loads malicious content
- Chrome's WebML component processes the untrusted input without proper validation
- Out-of-bounds memory write occurs, potentially corrupting adjacent memory regions
- This can result in integrity violations and application instability
The vulnerability manifests in the WebML input processing routines where boundary validation is insufficient. For detailed technical analysis, refer to the Chromium Issue Tracker Entry and the Google Chrome Desktop Update advisory.
Detection Methods for CVE-2026-5915
Indicators of Compromise
- Unexpected Chrome crashes or instability when visiting specific websites
- Memory corruption errors reported in Chrome's crash logs related to WebML operations
- Anomalous WebML API usage patterns in browser telemetry
- Suspicious HTML pages containing unusual WebML API calls with malformed parameters
Detection Strategies
- Monitor for Chrome process crashes with memory corruption signatures in crash dumps
- Implement web proxy analysis to detect suspicious HTML content with malformed WebML invocations
- Deploy endpoint detection rules to identify exploitation attempts targeting WebML APIs
- Analyze browser extension and content security policy violations that may indicate malicious page loading
Monitoring Recommendations
- Enable Chrome's built-in crash reporting and review crash logs for WebML-related errors
- Monitor network traffic for delivery of HTML pages with suspicious machine learning API calls
- Configure SIEM rules to correlate browser crash events with recently visited URLs
- Review browser process behavior for abnormal memory access patterns
How to Mitigate CVE-2026-5915
Immediate Actions Required
- Update Google Chrome to version 147.0.7727.55 or later immediately
- Enable automatic updates in Chrome to ensure timely security patches
- Restrict access to untrusted websites and implement URL filtering where possible
- Consider disabling WebML features via Chrome flags if updates cannot be applied immediately
Patch Information
Google has addressed this vulnerability in Chrome version 147.0.7727.55 released in April 2026. The fix implements proper input validation for WebML operations, preventing out-of-bounds memory writes when processing untrusted input data.
Organizations should prioritize updating all Chrome installations across their environment. The official patch information is available in the Google Chrome Desktop Update announcement.
Workarounds
- Restrict browser access to trusted websites only using web filtering solutions
- Disable experimental web platform features including WebML via chrome://flags if available
- Implement Content Security Policy headers on internal web applications to limit external content loading
- Use browser isolation technologies to contain potential exploitation attempts
# Check current Chrome version
google-chrome --version
# Force Chrome update via command line (Linux)
sudo apt update && sudo apt upgrade google-chrome-stable
# Verify Chrome version meets minimum requirement (147.0.7727.55 or later)
# If version is below 147.0.7727.55, update immediately
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
