CVE-2021-4100
📋 TL;DR
This vulnerability in ANGLE (Almost Native Graphics Layer Engine) in Google Chrome allows a remote attacker to potentially exploit heap corruption through a crafted HTML page. Attackers could execute arbitrary code or cause denial of service. Users of affected Chrome versions are at risk when visiting malicious websites.
💻 Affected Systems
- Google Chrome
- Chromium-based browsers
📦 What is this software?
Chrome by Google
Google Chrome is the world's most popular web browser, used by over 3 billion users globally across Windows, macOS, Linux, Android, and iOS platforms. As a Chromium-based browser developed by Google, Chrome dominates the browser market with approximately 65% market share, making it a critical compon...
Learn more about Chrome →⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to full system compromise, data theft, or ransomware deployment.
Likely Case
Browser crash/denial of service, potential information disclosure, or limited code execution in browser sandbox.
If Mitigated
Browser crash only, with sandbox preventing system-level compromise.
🎯 Exploit Status
Requires crafting specific HTML/WebGL content but no authentication needed. Heap corruption vulnerabilities often lead to reliable exploits.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 96.0.4664.110 and later
Vendor Advisory: https://chromereleases.googleblog.com/2021/12/stable-channel-update-for-desktop_13.html
Restart Required: Yes
Instructions:
1. Open Chrome. 2. Click three-dot menu → Help → About Google Chrome. 3. Chrome will automatically check for and install updates. 4. Click 'Relaunch' to restart Chrome with the patched version.
🔧 Temporary Workarounds
Disable WebGL
allPrevents ANGLE from processing malicious WebGL content that could trigger the vulnerability.
chrome://flags → Search 'WebGL' → Set 'WebGL 2.0' to Disabled
chrome://flags → Search 'WebGL' → Set 'WebGL Draft Extensions' to Disabled
Enable Site Isolation
allLimits impact by isolating websites in separate processes.
chrome://flags → Search 'Site Isolation' → Enable 'Site Isolation'
🧯 If You Can't Patch
- Use alternative browsers until Chrome can be updated.
- Implement network filtering to block known malicious websites and restrict access to untrusted sites.
🔍 How to Verify
Check if Vulnerable:
Check Chrome version: If version is less than 96.0.4664.110, system is vulnerable.Check Version:
chrome://version (look for 'Google Chrome' version number)Verify Fix Applied:
Confirm Chrome version is 96.0.4664.110 or higher after update.📡 Detection & Monitoring
Log Indicators:
- Chrome crash reports with ANGLE/WebGL-related stack traces
- Unexpected Chrome process terminations
Network Indicators:
- Requests to domains serving WebGL/HTML content followed by Chrome crashes
SIEM Query:
source="chrome_crash_reports" AND (process="chrome" OR process="gpu-process") AND message="ANGLE" OR message="heap corruption"