CVE-2021-24826 Explained : Impact and Mitigation

Custom Content Shortcode WordPress plugin before version 4.0.2 is vulnerable to Authenticated Stored Cross-Site Scripting, allowing Contributor+ or Admin+ users to execute XSS attacks. Here's what you need to know about CVE-2021-24826.

Understanding CVE-2021-24826

This CVE affects the Custom Content Shortcode WordPress plugin version 4.0.2 and below, presenting a risk of XSS attacks to certain user roles.

What is CVE-2021-24826?

The vulnerability in the Custom Content Shortcode plugin allows Contributor+ (v < 4.0.1) or Admin+ (v < 4.0.2) users to perform XSS attacks, even when unfiltered_html is disallowed.

The Impact of CVE-2021-24826

Admin+ users in single site blogs could exploit this vulnerability, posing a significant risk of executing XSS attacks.

Technical Details of CVE-2021-24826

The following technical details outline the vulnerability in the Custom Content Shortcode WordPress plugin:

Vulnerability Description

The plugin fails to escape custom fields before outputting them, enabling attackers to execute XSS attacks.

Affected Systems and Versions

Custom Content Shortcode versions less than 4.0.2 are impacted by this vulnerability.

Exploitation Mechanism

Contributor+ or Admin+ users can exploit this vulnerability to carry out Cross-Site Scripting attacks.

Mitigation and Prevention

To protect your system from CVE-2021-24826, consider the following protective measures:

Immediate Steps to Take

Update the Custom Content Shortcode plugin to version 4.0.2 or higher to patch the vulnerability.

Long-Term Security Practices

Regularly update plugins and follow security best practices to prevent XSS vulnerabilities.

Patching and Updates

Stay informed about security updates for all installed plugins to mitigate the risk of similar vulnerabilities.