CVE-2021-39320 : What You Need to Know

This article provides details about CVE-2021-39320, a vulnerability in the underConstruction plugin for WordPress.

Understanding CVE-2021-39320

CVE-2021-39320 is a reflected Cross-Site Scripting vulnerability affecting the underConstruction plugin <= 1.18 for WordPress.

What is CVE-2021-39320?

The underConstruction plugin <= 1.18 for WordPress is vulnerable to a reflected Cross-Site Scripting attack due to echoing out the raw value of

$GLOBALS['PHP_SELF']

in the ucOptions.php file.

The Impact of CVE-2021-39320

The vulnerability has a CVSS v3.1 base score of 6.1, with medium severity. It can allow an attacker to inject malicious code in the request path, potentially leading to Cross-Site Scripting attacks.

Technical Details of CVE-2021-39320

This section covers specific technical details of the CVE.

Vulnerability Description

The underConstruction plugin <= 1.18 echoes out the raw value of

$GLOBALS['PHP_SELF']

in the ucOptions.php file, making it susceptible to reflected Cross-Site Scripting attacks on certain configurations.

Affected Systems and Versions

Affected Product: underConstruction plugin
Vendor: Noah Kagan
Affected Version: <= 1.18 (custom version)

Exploitation Mechanism

The vulnerability can be exploited by injecting malicious code in the request path, which could be executed in the context of a user's browser.

Mitigation and Prevention

Learn how to mitigate and prevent this vulnerability.

Immediate Steps to Take

Update the underConstruction plugin to a version beyond 1.18.
Implement input validation to sanitize user inputs.
Monitor and filter user-supplied data for malicious content.

Long-Term Security Practices

Regularly scan your WordPress plugins for vulnerabilities.
Educate users on safe browsing habits to avoid executing arbitrary code.
Consider implementing Content Security Policy (CSP) headers on your website.

Patching and Updates

Stay informed about security patches and updates for the underConstruction plugin to address this vulnerability.