CVE-2020-4070 : What You Need to Know

In CSS Validator less than or equal to commit 54d68a1, a cross-site scripting vulnerability exists in URI handling. Users need to click on a crafted validator link to trigger it. The issue has been patched in commit e5c09a9.

Understanding CVE-2020-4070

This CVE involves a cross-site scripting vulnerability in the CSS Validator, affecting versions up to commit 54d68a1.

What is CVE-2020-4070?

Cross-site scripting vulnerability in CSS Validator allows attackers to execute malicious scripts on the victim's browser by injecting code into web pages.

The Impact of CVE-2020-4070

CVSS Base Score: 4.6 (Medium)
Attack Vector: Network
User Interaction: Required
Confidentiality Impact: Low
Integrity Impact: Low
Privileges Required: Low
Scope: Unchanged
Attack Complexity: Low
Availability Impact: None

Technical Details of CVE-2020-4070

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability in CSS Validator allows for cross-site scripting attacks through specially crafted URIs.

Affected Systems and Versions

Product: CSS Validator
Vendor: World Wide Web Consortium (W3C)
Affected Versions: <= 54d68a1

Exploitation Mechanism

To exploit this vulnerability, a user must interact with a maliciously crafted validator link, triggering the execution of unauthorized scripts.

Mitigation and Prevention

Protect systems and users from CVE-2020-4070 with these mitigation strategies.

Immediate Steps to Take

Update CSS Validator to commit e5c09a9 or later to apply the patch.
Educate users about the risks of clicking on unknown or suspicious links.

Long-Term Security Practices

Implement input validation mechanisms to sanitize user inputs and prevent script injection.
Regularly monitor and update web application security to address emerging threats.

Patching and Updates

Apply security patches promptly to address known vulnerabilities and protect systems from exploitation.