CVE-2023-38000 - Critical WordPress Core and Gutenberg Plugin Vulnerability: Authenticated Stored Cross-Site Scripting (XSS)

Security researchers recently discovered a critical vulnerability, assigned CVE-2023-38000, affecting multiple versions of WordPress Core and Gutenberg plugin. This vulnerability is an Authenticated Stored Cross-Site Scripting (XSS) issue and can have severe consequences for WordPress websites using the affected versions.

This post aims to provide comprehensive information regarding this vulnerability, including the affected versions, a code snippet demonstrating the vulnerability, links to original references, and exploit details. If you are a WordPress user, please ensure you read this post and take appropriate measures to protect your website.

Demonstrative Code Snippet

The vulnerability lies in the way WordPress Core sanitizes user input before storing and presenting it on the website. The following code snippet shows an example of how this vulnerability can be exploited by an attacker:

// The attacker inserts a malicious script as content within a post or comment
const maliciousScript = '<script>/* malicious code here */</script>';

// The vulnerable WordPress Core and Gutenberg plugin do not properly sanitize
// this input, allowing the attacker's script to be stored and displayed on the website
const unsanitizedData = jQuery('#comment').val(maliciousScript);

// When the stored script is executed on the target's browser, it can lead to
// severe consequences, such as stealing user's credentials or performing actions
// on behalf of the user.

Original References

Here are some helpful links for further reading and understanding of the CVE-2023-38000 vulnerability:

1. CVE-2023-38000 - NVD (National Vulnerability Database)
2. WordPress Core Security Release - Official Announcement
3. Gutenberg Plugin Security Advisory - GitHub

Exploit Details and Mitigation Steps

To exploit this vulnerability, an attacker must be authenticated, meaning they must have a user account on the website. These can be Contributor or higher-level accounts, which means that websites with user registration enabled are at a higher risk.

Since the vulnerability exploits the fact that input is not properly sanitized, a successful attack can result in malicious scripts being executed on the target's browser. This can lead to sensitive information theft, unauthorized changes made to the site, or other harmful actions.

To protect your WordPress website against this vulnerability, take the following steps

1. Update your WordPress Core to version 6.3.2 or later immediately. If you are using an earlier branch, choose the latest security release for your branch.

Add an additional layer of input sanitization to user inputs, such as comments and posts.

4. Disable user registration if not necessary for your website, or implement strict user roles and capabilities.

Closing Remarks

The CVE-2023-38000 vulnerability is a critical issue, but taking appropriate precautions and updating to the latest versions of WordPress Core and Gutenberg plugin should protect your website. Always be vigilant about your website's security and stay informed about vulnerabilities affecting your platform.

Timeline

Published on: 10/13/2023 10:15:09 UTC
Last modified on: 10/16/2023 17:04:06 UTC