CVE-2021-39318 : Security Advisory and Response

This CVE-2021-39318 article provides insights into a security vulnerability in the H5P CSS Editor WordPress plugin.

Understanding CVE-2021-39318

This section delves into the details of the vulnerability affecting the H5P CSS Editor plugin.

What is CVE-2021-39318?

The H5P CSS Editor WordPress plugin is susceptible to Reflected Cross-Site Scripting through the h5p-css-file parameter in the ~/h5p-css-editor.php file, enabling malicious actors to insert arbitrary web scripts in versions up to and including 1.0.

The Impact of CVE-2021-39318

The vulnerability is rated with a CVSS v3.1 base score of 6.1 (Medium severity) due to its potential to lower confidentiality, integrity, and availability.

Technical Details of CVE-2021-39318

In this section, we explore the technical aspects surrounding CVE-2021-39318.

Vulnerability Description

The vulnerability in the H5P CSS Editor plugin allows attackers to execute Reflected Cross-Site Scripting attacks by manipulating the h5p-css-file parameter.

Affected Systems and Versions

Product: H5P CSS Editor
Vendor: H5P CSS Editor
Vulnerable Version: 1.0 and below (including custom 1.0 version)

Exploitation Mechanism

The attack complexity is rated as LOW, with an attack vector via NETWORK. User interaction is required, and the scope is CHANGED, demanding no special privileges.

Mitigation and Prevention

Discover how to address the CVE-2021-39318 vulnerability in the H5P CSS Editor WordPress plugin.

Immediate Steps to Take

Uninstall the H5P CSS Editor plugin from your WordPress site immediately to mitigate the risk of exploitation.

Long-Term Security Practices

Regularly update all plugins and themes on your WordPress site to prevent exposure to known vulnerabilities.

Patching and Updates

Ensure to install any available patches or updates provided by the plugin vendor to secure your WordPress site.