CVE-2023-30496 - MagePeople Team WpBusTicketly Plugin <= 5.2.5: Cross-site Scripting (XSS) Vulnerability Explained

This long-read post will shed light on the critical vulnerability found in MagePeople Team WpBusTicketly plugin versions <= 5.2.5, identified as CVE-2023-30496. We will provide an in-depth analysis of the exploit, share a code snippet demonstrating the issue, and discuss proper mitigation strategies to ensure the security of your WordPress website.

The insecure component, *MagePeople Team WpBusTicketly Plugin*, is widely used for online bus ticket management by various organizations, making it an attractive target for hackers. The vulnerability referred to as *Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')* or *XSS* for short, can potentially put sensitive information at risk and enable attackers to execute malicious scripts through a user's web browser.

>Original reference

> - MagePeople Team WPBusTicketly Plugin XSS (CVE-2023-30496)
> - NVD - CVE-2023-30496

Explaining the vulnerability

Cross-site Scripting (XSS) is a common web application security flaw that allows an attacker to inject malicious scripts, typically JavaScript, into a legitimate website or web application. These scripts can bypass various security mechanisms and execute on a victim's machine without their knowledge or consent.

CVE-2023-30496 relates to a persistent (stored) XSS vulnerability in the MagePeople Team WpBusTicketly plugin, as user input is not properly sanitized before being stored in the plugin's database. Consequently, this unsanitized data is rendered to other users, resulting in the execution of malicious scripts if such content is embedded into the user input.

Code snippet demonstrating the issue

To better understand the vulnerability, consider the following PHP code snippet extracted from the vulnerable WpBusTicketly plugin:

// WpBusTicketly.php
function save_ticket_info(){
  // ...
  $ticket_data = array(
    // ...
    'special_req' => sanitize_text_field($_POST['sp_req']),
    // ...
  );
}

In the save_ticket_info function, the plugin obtains user input for sp_req and attempts to sanitize it using the sanitize_text_field function. However, the sanitize_text_field function does not provide sufficient protection against XSS attacks, as it only removes line breaks, leading and trailing whitespace, and certain HTML tags, allowing attackers to insert malicious script tags.

Exploit details

Attackers can exploit this vulnerability by submitting malicious input containing an embedded script in the 'sp_req' field when creating or editing bus ticket details through the web interface. Once an authenticated user (e.g., an administrator, editor, or manager) views the affected ticket data in their browser, the embedded script would be executed, leading to various security consequences depending on the nature of the script. These outcomes include stealing sensitive information, redirecting users to malicious websites, modifying website content, or even gaining full control of the targeted site.

Here's a sample payload that demonstrates the vulnerability

<script>alert('XSS vulnerability exploited')</script>

Mitigation

To mitigate this vulnerability, it is highly recommended to update the WpBusTicketly plugin to the latest version. If an update is not immediately available or you are unable to update for some reason, a more reliable sanitation method such as wp_kses should be implemented in the WpBusTicketly.php file. This function will remove any unsafe code from user input, reducing the risk of XSS vulnerabilities.

// WpBusTicketly.php
function save_ticket_info(){
  // ...
  // Replace sanitize_text_field with wp_kses
  $allowed_html = array(
    'a' => array(
      'href' => array(),
      'title' => array()
    ),
    // Add any other HTML elements and attributes that are allowed
  );
  $ticket_data['special_req'] = wp_kses($_POST['sp_req'], $allowed_html);
}

In conclusion, web developers and administrators must stay vigilant and keep their plugins and themes up to date to protect their websites against potential attacks. By following security best practices and adopting a proactive approach, it is possible to minimize the attack surface and ensure the safety of your WordPress site and its users. Stay safe!

Timeline

Published on: 11/22/2023 20:15:08 UTC
Last modified on: 11/29/2023 02:29:39 UTC