CVE-2025-4956: Pro Bulk Watermark Path Traversal Vulnerability

CVE-2025-4956 Overview

CVE-2025-4956 is a path traversal vulnerability in the AA-Team Pro Bulk Watermark Plugin for WordPress. The flaw affects all versions up to and including 2.0. An authenticated attacker with low privileges can traverse directories using crafted .../...// sequences to access files outside the plugin's intended directory scope. The vulnerability is classified under CWE-35: Path Traversal: '.../...//' and is exploitable over the network without user interaction.

Critical Impact
Authenticated attackers can read arbitrary files on the WordPress server, exposing configuration data, credentials, and other sensitive content within reach of the web server process.

Affected Products

AA-Team Pro Bulk Watermark Plugin for WordPress (all versions from n/a through 2.0)
WordPress installations using the vulnerable pro-watermark component
Sites where low-privileged users can access plugin functionality

Discovery Timeline

2025-08-30 - CVE-2025-4956 published to the National Vulnerability Database
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-4956

Vulnerability Analysis

The vulnerability stems from insufficient sanitization of user-supplied path input within the Pro Bulk Watermark Plugin. The plugin fails to normalize sequences such as .../...//, which bypass naive filters that strip only standard ../ patterns. When a filter removes ../ once without recursion, the residual characters in .../...// recombine into a valid traversal sequence.

Exploitation requires authenticated access with low privileges, meaning any user role that can invoke the affected plugin endpoints qualifies. The impact is limited to confidentiality — an attacker can read files accessible to the web server user but cannot modify data or disrupt availability through this flaw alone.

Exposed files may include wp-config.php, containing database credentials and authentication salts. Disclosure of these secrets enables secondary attacks including database compromise and session forgery.

Root Cause

The root cause is improper input validation in file path handling routines within the plugin, categorized as [CWE-35]. The sanitization logic does not perform recursive or canonical path resolution before file system operations, allowing crafted traversal sequences to escape the intended directory.

Attack Vector

The attack vector is network-based through the WordPress HTTP interface. An attacker authenticates to WordPress with a low-privileged account, then sends a request to a plugin endpoint containing the traversal payload in a file or path parameter. The server processes the request, resolves the manipulated path, and returns file contents from outside the plugin directory. Refer to the Patchstack Vulnerability Report for additional technical details.

Detection Methods for CVE-2025-4956

Indicators of Compromise

HTTP requests to Pro Bulk Watermark Plugin endpoints containing .../...//, ..%2f, or encoded traversal sequences in query or POST parameters
Web server access logs showing successful reads of files such as wp-config.php, .htaccess, or /etc/passwd following plugin requests
Unusual file access patterns originating from authenticated low-privileged WordPress accounts

Detection Strategies

Inspect WordPress and web server logs for traversal patterns targeting the pro-watermark plugin path
Deploy Web Application Firewall (WAF) rules that decode and normalize paths before matching against traversal signatures
Correlate authentication events for low-privileged accounts with plugin API calls containing suspicious path parameters

Monitoring Recommendations

Enable file integrity monitoring on wp-config.php and other sensitive files within the WordPress root
Alert on repeated 200-status responses to plugin endpoints from the same authenticated session
Forward WordPress and PHP error logs to a centralized platform for correlation with authentication telemetry

How to Mitigate CVE-2025-4956

Immediate Actions Required

Disable or uninstall the Pro Bulk Watermark Plugin until a patched version is confirmed available from AA-Team
Audit WordPress user accounts and revoke unnecessary access from low-privileged roles that can interact with the plugin
Rotate WordPress secrets, database credentials, and API keys if exploitation is suspected

Patch Information

No vendor-supplied patch is referenced in the NVD entry at time of publication. Monitor the Patchstack Vulnerability Report and the AA-Team plugin distribution channel for a fixed release beyond version 2.0.

Workarounds

Restrict plugin access at the web server level using authentication rules or IP allowlists
Deploy WAF rules that normalize URL-encoded and multi-dot traversal sequences before request handoff to PHP
Configure open_basedir in PHP to constrain file system access to the WordPress document root

bash

# Configuration example: restrict PHP file access via open_basedir
# Add to php.ini or site-specific configuration
open_basedir = "/var/www/wordpress/:/tmp/"

# Example nginx location block to block traversal patterns
location ~* /wp-content/plugins/pro-watermark/ {
    if ($args ~* "(\.\./|\.\.\.//|%2e%2e)") {
        return 403;
    }
}