CVE-2025-4828: Support Board Path Traversal Vulnerability

CVE-2025-4828 Overview

CVE-2025-4828 is a critical arbitrary file deletion vulnerability affecting the Support Board plugin for WordPress. The vulnerability exists due to insufficient file path validation in the sb_file_delete function, allowing attackers to delete arbitrary files on the server. When critical files such as wp-config.php are deleted, this can directly lead to remote code execution, as the WordPress installation enters a reinstallation state that attackers can exploit.

This vulnerability is particularly dangerous because it can be exploited without authentication when chained with CVE-2025-4855, creating a complete attack chain that requires no prior access to the WordPress site.

Critical Impact

Unauthenticated attackers can delete arbitrary files on the server, potentially leading to complete site takeover through remote code execution when critical WordPress configuration files are removed.

Affected Products

• Schiocco Support Board plugin for WordPress versions up to and including 3.8.0
• WordPress installations with the Support Board help desk and chat plugin installed
• All WordPress sites using vulnerable versions regardless of configuration

Discovery Timeline

• 2025-07-09 - CVE-2025-4828 published to NVD
• 2025-07-14 - Last updated in NVD database

Technical Details for CVE-2025-4828

Vulnerability Analysis

This vulnerability is classified as CWE-22 (Path Traversal), a category of security flaws where user-supplied input is not properly sanitized before being used in file system operations. The sb_file_delete function in the Support Board plugin fails to adequately validate the file path parameter before performing deletion operations.

The impact of this vulnerability is severe. An attacker can leverage the path traversal flaw to escape the intended directory and delete any file accessible by the web server process. The most damaging attack scenario involves deleting the wp-config.php file, which contains the WordPress database credentials and security keys. When this file is removed, WordPress enters a fresh installation state, allowing an attacker to complete the setup process with their own database and gain administrative control.

The vulnerability can be exploited remotely over the network without any user interaction required. No authentication is needed when the attacker chains this vulnerability with CVE-2025-4855, making it accessible to any threat actor with network access to the target WordPress site.

Root Cause

The root cause of CVE-2025-4828 is insufficient input validation and path sanitization in the sb_file_delete function. The function accepts user-controlled file path parameters without properly validating that the requested file resides within the intended plugin or upload directory boundaries.

Specifically, the function fails to:

• Canonicalize the file path to resolve directory traversal sequences (e.g., ../)
• Validate that the resolved path falls within an allowed directory
• Implement proper access controls to restrict which files can be deleted

Attack Vector

The attack vector for this vulnerability is network-based, allowing remote exploitation. An attacker can craft malicious requests to the vulnerable endpoint containing path traversal sequences that navigate outside the intended directory structure.

The exploitation flow typically involves:

1. The attacker identifies a WordPress site running a vulnerable version of the Support Board plugin
2. If authentication is required, the attacker first exploits CVE-2025-4855 to bypass authentication
3. The attacker sends a request to the file deletion endpoint with a crafted path containing traversal sequences such as ../../wp-config.php
4. The sb_file_delete function processes the request without proper validation and deletes the specified file
5. With wp-config.php deleted, the attacker accesses the WordPress site which now presents the installation wizard
6. The attacker completes the installation with their controlled database credentials, gaining administrative access

The vulnerability mechanism relies on insufficient path canonicalization. When the function receives a path like uploads/../../wp-config.php, it should resolve this to the actual filesystem location and verify it remains within allowed boundaries. The vulnerable implementation fails to perform this validation, allowing arbitrary file access and deletion.

Detection Methods for CVE-2025-4828

Indicators of Compromise

• Missing wp-config.php or other critical WordPress core files without legitimate administrative action
• Web server error logs showing attempts to access non-existent WordPress configuration files
• Access logs containing requests to Support Board plugin endpoints with path traversal patterns (../, ..%2f, ..%252f)
• Unexpected WordPress installation wizard appearing on established sites
• Database connection errors on previously functioning WordPress installations

Detection Strategies

• Monitor web server access logs for requests to /wp-content/plugins/support-board/ endpoints containing directory traversal sequences
• Implement Web Application Firewall (WAF) rules to detect and block path traversal patterns in request parameters
• Configure file integrity monitoring (FIM) to alert on unauthorized deletion of critical WordPress files
• Deploy SentinelOne Singularity to detect suspicious file system operations and unauthorized file deletions

Monitoring Recommendations

• Enable verbose logging for WordPress and the Support Board plugin to capture detailed request information
• Set up alerts for any modifications to critical WordPress files including wp-config.php, .htaccess, and core installation files
• Monitor for anomalous patterns of file deletion requests targeting the Support Board plugin
• Implement real-time file integrity monitoring with automated alerting capabilities

How to Mitigate CVE-2025-4828

Immediate Actions Required

• Update the Support Board plugin to a patched version immediately if one is available from the vendor
• If no patch is available, deactivate and remove the Support Board plugin until a fix is released
• Review web server logs to determine if the vulnerability has been exploited
• Verify the integrity of critical WordPress files, particularly wp-config.php
• Implement WAF rules to block path traversal attempts targeting the plugin

Patch Information

At the time of publication, organizations should check the CodeCanyon Help Desk Plugin page for the latest version and security updates. The Wordfence Vulnerability Report provides additional details and remediation guidance.

All versions up to and including 3.8.0 are confirmed vulnerable. Administrators should update to the latest available version that addresses this vulnerability.

Workarounds

• Temporarily deactivate the Support Board plugin if immediate patching is not possible
• Implement server-level access controls to restrict access to the plugin's file management endpoints
• Deploy a Web Application Firewall with rules to detect and block path traversal sequences in requests
• Configure file system permissions to make critical WordPress files immutable where operationally feasible

# Configuration example - Restrict write access to wp-config.php
chmod 400 /var/www/html/wp-config.php
chown root:root /var/www/html/wp-config.php

# Apache: Block path traversal in .htaccess
RewriteEngine On
RewriteCond %{QUERY_STRING} (\.\./|\.\.%2f|\.\.%252f) [NC]
RewriteRule .* - [F,L]