CVE-2021-4065
📋 TL;DR
This vulnerability is a use-after-free memory corruption flaw in Chrome's autofill feature that allows attackers to potentially execute arbitrary code or cause crashes. It affects all users running Chrome versions before 96.0.4664.93. Attackers can exploit this by tricking users into visiting a malicious webpage.
💻 Affected Systems
- Google Chrome
📦 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 leading to full system compromise, data theft, or ransomware deployment.
Likely Case
Browser crash (denial of service) or limited memory corruption leading to information disclosure.
If Mitigated
No impact if Chrome is patched or if exploit attempts are blocked by security controls.
🎯 Exploit Status
Exploitation requires user interaction (visiting a malicious page). No public exploit code is known, but use-after-free vulnerabilities are commonly exploited.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 96.0.4664.93
Vendor Advisory: https://chromereleases.googleblog.com/2021/12/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 and install updates. 4. Click 'Relaunch' to restart Chrome with the patched version.
🔧 Temporary Workarounds
Disable Autofill
allTemporarily disable Chrome's autofill feature to prevent exploitation.
Use Browser Sandboxing
allRun Chrome in a sandboxed environment to limit potential damage from exploitation.
🧯 If You Can't Patch
- Block access to untrusted websites using web filtering or firewall rules.
- Implement application whitelisting to prevent unauthorized code execution.
🔍 How to Verify
Check if Vulnerable:
Check Chrome version: if it's below 96.0.4664.93, it's vulnerable.Check Version:
chrome://version/ (in Chrome address bar) or 'google-chrome --version' (Linux terminal)Verify Fix Applied:
Confirm Chrome version is 96.0.4664.93 or higher after update.📡 Detection & Monitoring
Log Indicators:
- Chrome crash reports in system logs
- Unexpected Chrome process termination events
Network Indicators:
- Outbound connections to suspicious domains following Chrome crashes
- HTTP requests to known exploit hosting sites
SIEM Query:
source="chrome_crash_logs" AND event_type="crash" AND version<"96.0.4664.93"🔗 References
- https://chromereleases.googleblog.com/2021/12/stable-channel-update-for-desktop.html
- https://crbug.com/1273674
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3W46HRT2UVHWSLZB6JZHQF6JNQWKV744/
- https://security.gentoo.org/glsa/202208-25
- https://www.debian.org/security/2022/dsa-5046
- https://chromereleases.googleblog.com/2021/12/stable-channel-update-for-desktop.html
- https://crbug.com/1273674
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3W46HRT2UVHWSLZB6JZHQF6JNQWKV744/
- https://security.gentoo.org/glsa/202208-25
- https://www.debian.org/security/2022/dsa-5046
