CVE-2021-30512 – This is a use-after-free vulnerability in Googl... (How to Fix)

Q: What is the severity of CVE-2021-30512?

CVE-2021-30512 has a CVSS score of 8.8 (HIGH). This is a use-after-free vulnerability in Google Chrome's Notifications feature that allows heap corruption. Attackers who have already compromised the renderer process can exploit this via a crafted HTML page to potentially execute arbitrary code. All Chrome users prior to version 90.0.4430.212 are affected.

📋 TL;DR

This is a use-after-free vulnerability in Google Chrome's Notifications feature that allows heap corruption. Attackers who have already compromised the renderer process can exploit this via a crafted HTML page to potentially execute arbitrary code. All Chrome users prior to version 90.0.4430.212 are affected.

💻 Affected Systems

Products:

Google Chrome

Versions: All versions prior to 90.0.4430.212

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

Default Config Vulnerable: ⚠️ Yes

Notes: Requires renderer process compromise first, which typically involves another vulnerability chain.

📦 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...

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⚠️ Risk & Real-World Impact

🔴

Worst Case

Remote code execution leading to full system compromise, data theft, or ransomware deployment.

🟠

Likely Case

Arbitrary code execution within the Chrome sandbox, potentially leading to privilege escalation or lateral movement.

🟢

If Mitigated

Limited impact due to Chrome's sandboxing, with potential denial of service or information disclosure.

🌐 Internet-Facing: HIGH - Attackers can deliver exploits via malicious websites or ads.

🏢 Internal Only: MEDIUM - Requires user interaction with malicious content, but internal threats could exploit it.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: LIKELY

Unauthenticated Exploit: ⚠️ Yes

Complexity: MEDIUM

Requires chaining with another vulnerability to compromise renderer process first. Often used in exploit chains.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: 90.0.4430.212 and later

Vendor Advisory: https://chromereleases.googleblog.com/2021/05/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.

🔧 Temporary Workarounds

Disable Notifications

all

Disable Chrome notifications to prevent exploitation via this vector

chrome://settings/content/notifications → Toggle 'Sites can ask to send notifications' to off

Use Chrome Sandboxing

all

Ensure Chrome sandbox is enabled to limit impact

Verify sandbox is enabled in chrome://sandbox/

🧯 If You Can't Patch

Use alternative browsers until patching is possible
Implement network filtering to block malicious websites and ads

🔍 How to Verify

Check if Vulnerable:

Check Chrome version: If version is below 90.0.4430.212, system is vulnerable.

Check Version:

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

Verify Fix Applied:

Verify Chrome version is 90.0.4430.212 or higher.

📡 Detection & Monitoring

Log Indicators:

Chrome crash reports with memory corruption signatures
Unexpected renderer process terminations

Network Indicators:

Connections to known exploit delivery domains
Suspicious JavaScript execution patterns

SIEM Query:

source="chrome" AND (event="crash" OR event="process_termination") AND process="chrome_renderer"

📊 Metadata

CVE ID: CVE-2021-30512

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: June 4, 2021

Last Updated: November 21, 2024

🔗 References

https://chromereleases.googleblog.com/2021/05/stable-channel-update-for-desktop.html Release Notes,Vendor Advisory
https://crbug.com/1200019 Exploit,Issue Tracking,Patch,Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ETMZL6IHCTCTREEL434BQ4THQ7EOHJ43/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PAT6EOXVQFE6JFMFQF4IKAOUQSHMHL54/
https://security.gentoo.org/glsa/202107-06 Third Party Advisory
https://chromereleases.googleblog.com/2021/05/stable-channel-update-for-desktop.html Release Notes,Vendor Advisory
https://crbug.com/1200019 Exploit,Issue Tracking,Patch,Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ETMZL6IHCTCTREEL434BQ4THQ7EOHJ43/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PAT6EOXVQFE6JFMFQF4IKAOUQSHMHL54/
https://security.gentoo.org/glsa/202107-06 Third Party Advisory

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🔗 Related Vulnerabilities

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