CVE-2023-4779 : Exploit Details and Defense Strategies

This CVE-2023-4779 article provides a detailed overview of a security vulnerability identified in the User Submitted Posts plugin for WordPress.

Understanding CVE-2023-4779

The CVE-2023-4779 vulnerability is related to Stored Cross-Site Scripting found in the User Submitted Posts plugin for WordPress. This vulnerability allows authenticated attackers with contributor-level and above permissions to inject arbitrary web scripts using the plugin's [usp_gallery] shortcode.

What is CVE-2023-4779?

The User Submitted Posts plugin for WordPress is susceptible to Stored Cross-Site Scripting due to insufficient input sanitization and output escaping on user-supplied attributes like 'before'. This flaw enables attackers to insert malicious scripts into pages that execute whenever a user accesses the compromised page.

The Impact of CVE-2023-4779

The impact of this vulnerability is rated as MEDIUM according to CVSS:3.1. Attackers with the necessary permissions can exploit this vulnerability to execute arbitrary scripts on compromised pages, potentially leading to unauthorized actions or data theft.

Technical Details of CVE-2023-4779

The User Submitted Posts plugin for WordPress up to version 20230811 is affected by this vulnerability. Below are more technical details:

Vulnerability Description

The vulnerability arises from the lack of proper input sanitization and output escaping on the plugin's [usp_gallery] shortcode, allowing attackers to inject malicious scripts.

Affected Systems and Versions

The vulnerability affects User Submitted Posts plugin for WordPress versions up to and including 20230811.

Exploitation Mechanism

Authenticated attackers with contributor-level and above permissions can exploit this vulnerability by injecting malicious scripts using the plugin's [usp_gallery] shortcode.

Mitigation and Prevention

To mitigate the CVE-2023-4779 vulnerability in the User Submitted Posts plugin, consider the following steps:

Immediate Steps to Take

Update the User Submitted Posts plugin to a version beyond 20230811 to eliminate the vulnerability.
Regularly monitor for any unusual activities or malicious scripts injected into pages.

Long-Term Security Practices

Educate users with contributor-level and above permissions on safe practices when using shortcodes and handling user-submitted content.
Conduct regular security audits and use security plugins to enhance WordPress website security.

Patching and Updates

Stay informed about security updates and patches released by the plugin developer for the User Submitted Posts plugin. Ensure timely installation of these updates to protect against known vulnerabilities.