CVE-2021-37959 – This is a use-after-free vulnerability in Googl... (How to Fix)

Q: What is the severity of CVE-2021-37959?

CVE-2021-37959 has a CVSS score of 8.8 (HIGH). This is a use-after-free vulnerability in Google Chrome's Task Manager that allows an attacker to potentially exploit heap corruption. Attackers can trigger this by convincing users to interact with a malicious HTML page through a series of gestures. All users running vulnerable versions of Chrome are affected.

📋 TL;DR

This is a use-after-free vulnerability in Google Chrome's Task Manager that allows an attacker to potentially exploit heap corruption. Attackers can trigger this by convincing users to interact with a malicious HTML page through a series of gestures. All users running vulnerable versions of Chrome are affected.

💻 Affected Systems

Products:

Google Chrome

Versions: All versions prior to 94.0.4606.54

Operating Systems: Windows, Linux, macOS, Android, iOS

Default Config Vulnerable: ⚠️ Yes

Notes: All Chrome installations with default settings are vulnerable. Affects all platforms where Chrome runs.

📦 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 complete system compromise, data theft, or ransomware deployment.

🟠

Likely Case

Browser crash, denial of service, or limited information disclosure from memory corruption.

🟢

If Mitigated

No impact if Chrome is updated to patched version or if exploit attempts are blocked by security controls.

🌐 Internet-Facing: HIGH

🏢 Internal Only: MEDIUM

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ✅ No

Complexity: MEDIUM

Requires user interaction (series of gestures) and crafted HTML page. No public exploit code available.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: 94.0.4606.54 and later

Vendor Advisory: https://chromereleases.googleblog.com/2021/09/stable-channel-update-for-desktop_21.html

Restart Required: Yes

Instructions:

1. Open Chrome 2. Click menu (three dots) 3. Go to Help > About Google Chrome 4. Chrome will automatically check for and install updates 5. Click Relaunch to restart Chrome

🔧 Temporary Workarounds

Disable JavaScript

all

Prevents execution of malicious JavaScript that could trigger the vulnerability

Use Chrome sandboxing

all

Ensure Chrome sandbox is enabled to limit impact of potential exploitation

🧯 If You Can't Patch

Restrict access to untrusted websites using web filtering or proxy controls
Implement application whitelisting to prevent unauthorized code execution

🔍 How to Verify

Check if Vulnerable:

Check Chrome version in Help > About Google Chrome. If version is below 94.0.4606.54, system is vulnerable.

Check Version:

chrome://version/ or 'google-chrome --version' on Linux

Verify Fix Applied:

Confirm Chrome version is 94.0.4606.54 or higher in Help > About Google Chrome.

📡 Detection & Monitoring

Log Indicators:

Chrome crash reports
Unexpected process termination events
Memory access violation logs

Network Indicators:

Requests to suspicious domains hosting HTML pages
Unusual user interaction patterns with web content

SIEM Query:

source="chrome" AND (event_type="crash" OR message="*use-after-free*" OR message="*heap corruption*")

📊 Metadata

CVE ID: CVE-2021-37959

CVSS v3 Score: 8.8 (HIGH)

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CWE: CWE-416

Published: October 8, 2021

Last Updated: November 21, 2024

🔗 References

https://chromereleases.googleblog.com/2021/09/stable-channel-update-for-desktop_21.html Release Notes,Vendor Advisory
https://crbug.com/1229625 Permissions Required,Vendor Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4DDW7HAHTS3SDVXBQUY4SURELO5D4X7R/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PM7MOYYHJSWLIFZ4TPJTD7MSA3HSSLV2/
https://www.debian.org/security/2022/dsa-5046 Third Party Advisory
https://chromereleases.googleblog.com/2021/09/stable-channel-update-for-desktop_21.html Release Notes,Vendor Advisory
https://crbug.com/1229625 Permissions Required,Vendor Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4DDW7HAHTS3SDVXBQUY4SURELO5D4X7R/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PM7MOYYHJSWLIFZ4TPJTD7MSA3HSSLV2/
https://www.debian.org/security/2022/dsa-5046 Third Party Advisory

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🔗 Related Vulnerabilities

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