CVE-2022-50936: WBCE CMS Authenticated RCE Vulnerability

CVE-2022-50936 Overview

CVE-2022-50936 is an authenticated remote code execution (RCE) vulnerability affecting WBCE CMS version 1.5.2. The vulnerability exists in the droplet upload functionality within the admin panel, allowing authenticated attackers to upload and execute arbitrary PHP code on the target server through specially crafted zip file payloads.

WBCE CMS is a fork of WebsiteBaker, designed as a simple and flexible content management system. The droplet feature allows administrators to extend CMS functionality through custom PHP code snippets. However, insufficient validation of uploaded droplet files enables attackers with admin panel access to achieve full server compromise.

Critical Impact

Authenticated attackers can execute arbitrary PHP code on vulnerable WBCE CMS servers, potentially leading to complete system compromise, data exfiltration, and lateral movement within the network.

Affected Products

• WBCE CMS version 1.5.2
• Earlier versions of WBCE CMS may also be affected

Discovery Timeline

• 2026-01-13 - CVE CVE-2022-50936 published to NVD
• 2026-01-13 - Last updated in NVD database

Technical Details for CVE-2022-50936

Vulnerability Analysis

This vulnerability is classified under CWE-434 (Unrestricted Upload of File with Dangerous Type). The WBCE CMS admin tools module contains a droplet upload feature that fails to properly validate the contents of uploaded zip files before extracting and processing them. Authenticated administrators can leverage this functionality to upload malicious PHP code disguised as legitimate droplet extensions.

The attack requires valid administrative credentials, but once authenticated, an attacker can craft a specially designed zip file containing PHP code that will be extracted to an accessible location on the web server. When the uploaded PHP file is subsequently accessed via a web request, the arbitrary code executes with the privileges of the web server process.

Root Cause

The root cause of this vulnerability is insufficient input validation and file type checking in the droplet upload handler. The application fails to:

1. Properly validate the contents of uploaded zip archives
2. Restrict the types of files that can be extracted from uploaded archives
3. Sanitize or sandbox extracted PHP code before execution

This allows attackers to bypass intended security controls and introduce malicious executable code into the CMS environment.

Attack Vector

The attack is network-based and requires prior authentication to the WBCE CMS admin panel. The exploitation workflow involves:

1. Attaining valid administrative credentials through brute force, credential stuffing, phishing, or other means
2. Navigating to the admin tools section where droplet upload functionality resides
3. Crafting a malicious zip file containing a PHP webshell or other malicious payload
4. Uploading the crafted zip file through the droplet installation interface
5. Accessing the extracted PHP file directly via the web server to trigger code execution

The vulnerability allows an attacker to execute code with the same privileges as the web server process, typically enabling file system access, database manipulation, and potential pivot points for further network compromise.

Detection Methods for CVE-2022-50936

Indicators of Compromise

• Unexpected PHP files appearing in the WBCE CMS droplets directory
• Suspicious zip file uploads through the admin panel with unusual naming conventions
• Web server logs showing direct access to newly created PHP files in droplet directories
• Anomalous outbound network connections from the web server process

Detection Strategies

• Monitor file system changes in the WBCE CMS installation directory, particularly in locations where droplets are stored
• Implement web application firewall (WAF) rules to detect malicious PHP code patterns in uploaded files
• Review admin panel access logs for unusual droplet upload activity
• Deploy endpoint detection to identify webshell behaviors such as command execution or file operations

Monitoring Recommendations

• Enable comprehensive logging for all admin panel activities in WBCE CMS
• Configure file integrity monitoring (FIM) on the CMS installation directory
• Set up alerts for new PHP file creation in web-accessible directories
• Monitor for suspicious process spawning from the web server process (e.g., cmd.exe, /bin/sh, curl, wget)

How to Mitigate CVE-2022-50936

Immediate Actions Required

• Audit all WBCE CMS admin accounts and enforce strong, unique passwords with multi-factor authentication where possible
• Review recently uploaded droplets and remove any suspicious or unrecognized files
• Restrict admin panel access to trusted IP addresses using firewall rules or .htaccess configurations
• Consider temporarily disabling the droplet upload functionality until a patch is available

Patch Information

Check the WBCE CMS GitHub Repository for the latest security updates and version releases. The WBCE Official Website and Downloads Page may contain updated versions addressing this vulnerability.

Additional vulnerability information is available through the VulnCheck WBCE CMS RCE Advisory and Exploit-DB #50707.

Workarounds

• Implement network-level access controls to restrict admin panel access to authorized personnel only
• Deploy a web application firewall (WAF) with rules to block malicious file uploads
• Remove or rename the droplet upload functionality if not operationally required
• Run the web server with minimal privileges to limit the impact of successful exploitation
• Regularly backup the CMS installation and database to enable rapid recovery in case of compromise