CVE-2021-38001
📋 TL;DR
This vulnerability is a type confusion flaw in Chrome's V8 JavaScript engine that could allow an attacker to trigger heap corruption by tricking the browser into misinterpreting data types. Attackers could exploit this via malicious web pages to potentially execute arbitrary code or crash the browser. All users of affected Chrome versions are vulnerable when visiting crafted HTML pages.
💻 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 →Fedora by Fedoraproject
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with the same privileges as the Chrome process, potentially leading to full system compromise, data theft, or malware installation.
Likely Case
Browser crash (denial of service) or limited memory corruption that could be leveraged for information disclosure or further exploitation.
If Mitigated
No impact if Chrome is fully patched or if exploit attempts are blocked by security controls like web filtering or isolation.
🎯 Exploit Status
Exploitation requires user interaction (visiting a malicious page) but no authentication. Type confusion vulnerabilities in V8 have historically been exploited in the wild.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 95.0.4638.69 and later
Vendor Advisory: https://chromereleases.googleblog.com/2021/10/stable-channel-update-for-desktop_28.html
Restart Required: Yes
Instructions:
1. Open Chrome. 2. Click the 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 JavaScript
allPrevents execution of malicious JavaScript that could trigger the vulnerability
chrome://settings/content/javascript → toggle to 'Blocked'
Use Site Isolation
allLimits impact by isolating websites in separate processes
chrome://flags/#site-isolation-trial-opt-out → set to 'Disabled'
🧯 If You Can't Patch
- Deploy network-level URL filtering to block malicious sites
- Use application control to restrict Chrome usage to essential personnel only
🔍 How to Verify
Check if Vulnerable:
Check Chrome version via chrome://version and compare to 95.0.4638.69Check Version:
google-chrome --version (Linux), 'About Google Chrome' in menu (Windows/macOS)Verify Fix Applied:
Confirm Chrome version is 95.0.4638.69 or higher📡 Detection & Monitoring
Log Indicators:
- Chrome crash reports
- Unexpected process termination events
- Security event logs showing memory access violations
Network Indicators:
- Requests to known malicious domains hosting exploit code
- Unusual outbound connections from Chrome processes
SIEM Query:
source="chrome_logs" AND (event_type="crash" OR message="*V8*" OR message="*heap corruption*")🔗 References
- https://chromereleases.googleblog.com/2021/10/stable-channel-update-for-desktop_28.html
- https://crbug.com/1260577
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3W46HRT2UVHWSLZB6JZHQF6JNQWKV744/
- https://www.debian.org/security/2022/dsa-5046
- https://chromereleases.googleblog.com/2021/10/stable-channel-update-for-desktop_28.html
- https://crbug.com/1260577
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3W46HRT2UVHWSLZB6JZHQF6JNQWKV744/
- https://www.debian.org/security/2022/dsa-5046
