CVE-2021-21187 : Vulnerability Insights and Analysis

This article provides detailed information about CVE-2021-21187, a vulnerability in Google Chrome that allowed a remote attacker to perform domain spoofing.

Understanding CVE-2021-21187

CVE-2021-21187 is an insufficient data validation vulnerability in URL formatting in Google Chrome versions prior to 89.0.4389.72 that enabled a remote attacker to conduct domain spoofing through a crafted domain name.

What is CVE-2021-21187?

The vulnerability in URL formatting in Google Chrome allowed threat actors to engage in domain spoofing via IDN homographs by exploiting a flaw in how URLs were validated.

The Impact of CVE-2021-21187

This vulnerability could be exploited by a remote attacker to deceive users by displaying a malicious site's address as a legitimate one, potentially leading to phishing attacks and unauthorized information disclosure.

Technical Details of CVE-2021-21187

CVE ID: CVE-2021-21187 Vendor: Google Affected Product: Chrome Vulnerable Versions: Prior to 89.0.4389.72

Vulnerability Description

Insufficient data validation in URL formatting in Google Chrome versions before 89.0.4389.72 enabled domain spoofing through IDN homographs with a specially crafted domain name.

Affected Systems and Versions

Google Chrome versions prior to 89.0.4389.72 are impacted by this vulnerability.

Exploitation Mechanism

Remote attackers could exploit this vulnerability by creating malicious URLs with IDN homographs to trick users into visiting fake websites.

Mitigation and Prevention

To mitigate the risks associated with CVE-2021-21187, users and organizations are advised to take immediate steps and adopt long-term security practices to enhance their defense mechanisms.

Immediate Steps to Take

Update Google Chrome to version 89.0.4389.72 or later to patch the vulnerability.
Be cautious while clicking on URLs and avoid visiting suspicious or untrustworthy websites.

Long-Term Security Practices

Regularly update software and applications to ensure you have the latest security patches.
Educate users about the risks of phishing attacks and the importance of verifying website URLs.

Patching and Updates

Regularly check for security updates from Google Chrome and apply patches promptly to protect against known vulnerabilities.