CVE-2021-24759 : Exploit Details and Defense Strategies

PDF.js Viewer WordPress plugin version before 2.0.2 is vulnerable to stored Cross-Site Scripting (XSS) attacks that could be exploited by users with a low role such as Contributor.

Understanding CVE-2021-24759

This CVE refers to a security issue in the PDF.js Viewer WordPress plugin version prior to 2.0.2 that allows for stored Cross-Site Scripting attacks.

What is CVE-2021-24759?

The PDF.js Viewer WordPress plugin version before 2.0.2 is susceptible to Cross-Site Scripting (XSS) attacks due to unescaped shortcode and Gutenberg Block attributes.

The Impact of CVE-2021-24759

This vulnerability could be exploited by users with minimal permissions like Contributors to execute malicious scripts, potentially leading to unauthorized actions on the affected website.

Technical Details of CVE-2021-24759

This section delves into the specifics of the vulnerability, affected systems, and exploitation mechanisms.

Vulnerability Description

The PDF.js Viewer WordPress plugin version before 2.0.2 fails to properly escape certain shortcode and Gutenberg Block attributes, opening the door to Cross-Site Scripting (XSS) attacks.

Affected Systems and Versions

PDF.js Viewer version less than 2.0.2 is confirmed to be impacted by this vulnerability.

Exploitation Mechanism

Unauthorized users, including those with limited roles like Contributor, can exploit this vulnerability to inject and execute malicious scripts on the target website.

Mitigation and Prevention

Explore the steps to mitigate the risk of exploitation and prevent such vulnerabilities in the future.

Immediate Steps to Take

Update the PDF.js Viewer plugin to version 2.0.2 or higher to eliminate this vulnerability. Additionally, review user permissions to limit the impact of potential XSS attacks.

Long-Term Security Practices

Regularly monitor and update plugins, themes, and the WordPress core to maintain a secure website environment.

Patching and Updates

Stay informed about security updates and ensure timely patching of known vulnerabilities to safeguard your website from potential exploitation.