CVE-2023-5135 : What You Need to Know

This CVE-2023-5135, assigned by Wordfence, was published on September 26, 2023. It affects the "Simple Cloudflare Turnstile – CAPTCHA Alternative" plugin for WordPress, making it vulnerable to Stored Cross-Site Scripting in versions up to and including 1.23.1. The vulnerability arises from inadequate input sanitization and output escaping on user-supplied attributes, allowing authenticated attackers with contributor-level permissions or higher to inject malicious web scripts.

Understanding CVE-2023-5135

This section delves deeper into the specifics of CVE-2023-5135.

What is CVE-2023-5135?

CVE-2023-5135 is a vulnerability present in the Simple Cloudflare Turnstile plugin for WordPress, enabling attackers to execute stored Cross-Site Scripting attacks via a specific shortcode.

The Impact of CVE-2023-5135

The impact of this vulnerability is significant as it can be exploited by authenticated attackers with certain permissions to inject and execute arbitrary scripts on targeted pages when accessed by users.

Technical Details of CVE-2023-5135

In this section, we explore the technical aspects of CVE-2023-5135.

Vulnerability Description

The vulnerability stems from the lack of proper input sanitization and output escaping on user-supplied attributes within the 'gravity-simple-turnstile' shortcode in affected versions of the Simple Cloudflare Turnstile plugin.

Affected Systems and Versions

The affected system is the "Simple Cloudflare Turnstile – CAPTCHA Alternative" plugin for WordPress with versions up to and including 1.23.1.

Exploitation Mechanism

Attackers with contributor-level permissions or higher can exploit this vulnerability by injecting malicious web scripts through the plugin's shortcode, leading to Cross-Site Scripting attacks.

Mitigation and Prevention

Mitigating CVE-2023-5135 is crucial to maintaining WordPress site security. Here are some recommendations to address this vulnerability.

Immediate Steps to Take

Disable or uninstall the vulnerable Simple Cloudflare Turnstile plugin if not essential.
Apply any available patches or updates provided by the plugin developer promptly.
Educate site users about safe practices to reduce the risk of XSS attacks.

Long-Term Security Practices

Regularly update plugins and WordPress core to ensure the latest security fixes are in place.
Implement security plugins or web application firewalls to detect and block malicious scripts.
Conduct routine security audits and penetration testing to identify vulnerabilities proactively.

Patching and Updates

Stay informed about security advisories from plugin developers and promptly apply any patches or updates to mitigate known vulnerabilities like CVE-2023-5135. Regular monitoring and maintenance are essential to safeguard WordPress sites from potential security risks.