CVE-2021-30541
📋 TL;DR
This is a use-after-free vulnerability in Chrome's V8 JavaScript engine that allows remote attackers to potentially exploit heap corruption. Attackers can craft malicious HTML pages to trigger memory corruption, potentially leading to arbitrary code execution. All users running vulnerable versions of Google Chrome are affected.
💻 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 with the privileges of the Chrome process, potentially leading to full system compromise if combined with privilege escalation vulnerabilities.
Likely Case
Browser crash (denial of service) or limited information disclosure through memory corruption.
If Mitigated
No impact if Chrome is fully patched or if exploit attempts are blocked by security controls.
🎯 Exploit Status
Exploitation requires user interaction (visiting malicious website) but no authentication. Use-after-free vulnerabilities in V8 are commonly exploited in the wild.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 91.0.4472.164 and later
Vendor Advisory: https://chromereleases.googleblog.com/2021/07/stable-channel-update-for-desktop.html
Restart Required: Yes
Instructions:
1. Open Chrome. 2. Click the three-dot menu → Help → About Google Chrome. 3. Chrome will automatically check for updates and install version 91.0.4472.164 or later. 4. Click 'Relaunch' to restart Chrome with the update.
🔧 Temporary Workarounds
Disable JavaScript
allTemporarily disable JavaScript execution in Chrome to prevent exploitation
chrome://settings/content/javascript → Block
Use Site Isolation
allEnable Site Isolation to limit impact of renderer process compromises
chrome://flags/#enable-site-per-process → Enable
🧯 If You Can't Patch
- Use alternative browsers until Chrome can be updated
- Implement network filtering to block known malicious domains hosting exploit code
🔍 How to Verify
Check if Vulnerable:
Check Chrome version: if below 91.0.4472.164, system is vulnerableCheck Version:
chrome://versionVerify Fix Applied:
Confirm Chrome version is 91.0.4472.164 or higher📡 Detection & Monitoring
Log Indicators:
- Chrome crash reports with V8-related stack traces
- Unexpected Chrome process terminations
Network Indicators:
- Connections to suspicious domains followed by Chrome crashes
SIEM Query:
source="chrome_crash_reports" AND (process="chrome" OR process="renderer") AND message="V8"