CVE-2023-4021 Explained : Impact and Mitigation

This CVE-2023-4021 article provides insights into a security vulnerability found in the Modern Events Calendar Lite plugin for WordPress, impacting versions up to, but not including, 7.1.0. The vulnerability allows for Stored Cross-Site Scripting via Google API key and Calendar ID due to inadequate input sanitization and output escaping.

Understanding CVE-2023-4021

This section delves into the details of CVE-2023-4021, shedding light on the nature of the vulnerability and its potential impact on affected systems.

What is CVE-2023-4021?

CVE-2023-4021 refers to a Stored Cross-Site Scripting vulnerability in the Modern Events Calendar Lite plugin for WordPress. This vulnerability arises from inadequate input sanitization and output escaping, allowing attackers with administrator-level permissions or higher to inject malicious web scripts into pages.

The Impact of CVE-2023-4021

The impact of CVE-2023-4021 is significant as it enables authenticated attackers to execute arbitrary web scripts on injected pages. This vulnerability specifically affects multi-site installations and instances where unfiltered_html has been disabled, potentially leading to unauthorized script execution.

Technical Details of CVE-2023-4021

This section delves into the technical aspects of CVE-2023-4021, outlining the vulnerability description, affected systems, versions, and the exploitation mechanism.

Vulnerability Description

The vulnerability in the Modern Events Calendar Lite plugin for WordPress allows for Stored Cross-Site Scripting via Google API key and Calendar ID in versions prior to 7.1.0. It stems from insufficient input sanitization and output escaping, enabling attackers to inject malicious web scripts on vulnerable pages.

Affected Systems and Versions

The vulnerability affects installations of the Modern Events Calendar Lite plugin for WordPress up to version 7.1.0. Specifically, multi-site setups and instances where unfiltered_html has been disabled are at risk of exploitation.

Exploitation Mechanism

The exploitation of CVE-2023-4021 requires authenticated access with administrator-level permissions or above. Attackers can leverage the vulnerability to inject arbitrary web scripts, which will execute when users access the compromised pages.

Mitigation and Prevention

In this section, strategies to mitigate the risk posed by CVE-2023-4021 are discussed, focusing on immediate steps to take, long-term security practices, and the importance of patching and updates.

Immediate Steps to Take

Users are advised to update the Modern Events Calendar Lite plugin to version 7.1.0 or newer to mitigate the vulnerability. Additionally, restricting access to administrator privileges and closely monitoring website activities can help prevent unauthorized script injections.

Long-Term Security Practices

Implementing secure coding practices, conducting regular security audits, and staying informed about plugin updates and security advisories are essential long-term security measures to safeguard against potential vulnerabilities like CVE-2023-4021.

Patching and Updates

Regularly applying security patches and updates to the WordPress plugins installed on websites is crucial to addressing known vulnerabilities and enhancing overall security posture. Stay vigilant for security alerts and promptly install patches released by plugin developers to mitigate risks effectively.