CVE-2025-3923: WordPress PDA Plugin Info Disclosure Flaw

CVE-2025-3923 Overview

CVE-2025-3923 affects the Prevent Direct Access – Protect WordPress Files plugin for WordPress. The plugin is vulnerable to sensitive information exposure in all versions up to and including 2.8.8. The flaw resides in the generate_unique_string function, which produces file names with insufficient randomness. Unauthenticated attackers who can determine or predict the generated file name can retrieve files that the plugin was intended to protect. The weakness is categorized under CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor).

Critical Impact
Unauthenticated attackers can access protected WordPress files by predicting the weakly randomized file names generated by the plugin.

Affected Products

Prevent Direct Access – Protect WordPress Files plugin for WordPress
All plugin versions up to and including 2.8.8
WordPress sites relying on the plugin to restrict direct file access

Discovery Timeline

2025-04-25 - CVE-2025-3923 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-3923

Vulnerability Analysis

The Prevent Direct Access plugin protects uploaded files by relocating them to obfuscated paths. Access control relies on the unpredictability of the generated file name. The generate_unique_string function in includes/helper.php produces those names using insufficient randomness, which makes the resulting identifiers guessable or enumerable within a feasible search space.

Because the protection model depends entirely on file name secrecy, weak randomness collapses the security boundary. An attacker who successfully guesses a name can download the protected file over the network without authenticating. The impact is limited to confidentiality: files can be read, but the flaw does not permit modification or service disruption.

Root Cause

The root cause is the use of a low-entropy string generation routine to create security-sensitive identifiers. The plugin treats the output of generate_unique_string as an unguessable token, yet the generator does not use a cryptographically secure source of randomness with sufficient length. This constitutes an insecure random number generation flaw driving an information disclosure condition.

Attack Vector

An unauthenticated remote attacker issues HTTP requests against the target WordPress site to enumerate or predict file names produced by the plugin. Once a valid name is discovered, the attacker requests the corresponding URL and downloads the protected file. No user interaction, credentials, or elevated privileges are required. For technical details, see the WordPress Plugin Source Code and the Wordfence Vulnerability Report.

Detection Methods for CVE-2025-3923

Indicators of Compromise

High volumes of HTTP GET requests to plugin-protected file paths from a single source, indicative of file name enumeration.
Repeated 404 responses followed by a successful 200 response to a protected file URL.
Access to protected uploads from IP addresses that never authenticated to the WordPress site.

Detection Strategies

Inspect web server access logs for scanning patterns targeting the plugin's protected upload directories.
Correlate anomalous download activity with the absence of a preceding authenticated session or referrer from the site.
Alert on requests that iterate through similar file name patterns matching the plugin's naming scheme.

Monitoring Recommendations

Enable verbose access logging on the WordPress front-end web server and forward logs to a central analytics platform.
Baseline normal request rates to plugin-managed URLs and alert on deviations.
Track outbound data volumes from the WordPress host to identify bulk exfiltration of protected files.

How to Mitigate CVE-2025-3923

Immediate Actions Required

Update the Prevent Direct Access – Protect WordPress Files plugin to a version later than 2.8.8 once released by the vendor.
Audit the wp-content/uploads directory for files previously protected by the plugin and rotate or regenerate their file names after patching.
Restrict direct access to sensitive uploads at the web server layer as a defense-in-depth measure.

Patch Information

At the time of the NVD publication, all versions up to and including 2.8.8 are affected. Administrators should monitor the plugin's WordPress.org listing and the Wordfence Vulnerability Report for a fixed release and apply it as soon as it becomes available.

Workarounds

Enforce authentication on protected file paths via web server rules such as Apache .htaccess or Nginx location directives, rather than relying solely on file name obscurity.
Deploy a Web Application Firewall rule to rate-limit and block enumeration of URLs under the plugin's protected directories.
Temporarily move highly sensitive files outside the web root and serve them through an authenticated PHP handler until a patched plugin version is deployed.

bash

# Configuration example: Nginx rule to require authentication for protected uploads
location ^~ /wp-content/uploads/_pda/ {
    auth_basic "Restricted";
    auth_basic_user_file /etc/nginx/.htpasswd;
    limit_req zone=pda_zone burst=5 nodelay;
}