CVE-2025-39462: Smart Agreements LFI Vulnerability

CVE-2025-39462 Overview

CVE-2025-39462 is a Local File Inclusion (LFI) vulnerability affecting the Smart Agreements WordPress plugin developed by teamzt. The vulnerability stems from improper control of filename parameters used in PHP include/require statements, allowing attackers to include arbitrary local files on the server. This can lead to sensitive information disclosure, configuration file exposure, and potentially remote code execution if combined with other attack vectors.

Critical Impact

Attackers can exploit this LFI vulnerability to read sensitive server files, expose WordPress configuration details including database credentials, and potentially achieve code execution through log poisoning or other chained attack techniques.

Affected Products

• Smart Agreements WordPress Plugin version 1.0.3 and earlier
• WordPress installations running vulnerable Smart Agreements plugin versions

Discovery Timeline

• 2025-04-17 - CVE-2025-39462 published to NVD
• 2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-39462

Vulnerability Analysis

This vulnerability is classified under CWE-98 (Improper Control of Filename for Include/Require Statement in PHP Program). The Smart Agreements plugin fails to properly validate and sanitize user-supplied input before using it in PHP file inclusion functions. When an attacker can control or influence the filename parameter passed to include(), include_once(), require(), or require_once() functions, they can traverse the directory structure and include arbitrary files from the local filesystem.

The attack requires network access and some user interaction, making it moderately complex to exploit in real-world scenarios. However, successful exploitation grants the attacker access to highly sensitive information and can serve as a stepping stone to more severe attacks.

Root Cause

The root cause of this vulnerability lies in insufficient input validation within the Smart Agreements plugin. The plugin accepts user-controlled parameters that are subsequently used to construct file paths for PHP include statements without proper sanitization. This allows attackers to use directory traversal sequences (such as ../) to escape the intended directory and access files elsewhere on the filesystem.

Common targets for LFI attacks include:

• /etc/passwd for user enumeration
• wp-config.php for database credentials
• Log files for log poisoning attacks
• .htaccess files for configuration details

Attack Vector

The vulnerability is exploitable over the network, requiring an attacker to craft malicious HTTP requests that inject path traversal sequences into vulnerable parameters. The attack typically involves manipulating GET or POST parameters that control which template or file the plugin includes.

A typical attack flow involves the attacker identifying the vulnerable parameter, injecting directory traversal sequences to navigate to sensitive files, and then extracting the file contents through the application response. When combined with techniques like log poisoning or PHP filter wrappers, this vulnerability can be escalated to achieve remote code execution.

For detailed technical information about this vulnerability, refer to the Patchstack Vulnerability Report.

Detection Methods for CVE-2025-39462

Indicators of Compromise

• HTTP requests containing directory traversal sequences (../, ..%2f, %2e%2e/) targeting Smart Agreements plugin endpoints
• Access logs showing attempts to read system files like /etc/passwd or wp-config.php through plugin parameters
• Unusual file access patterns originating from web server processes
• Error logs indicating failed file inclusion attempts with traversal paths

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block requests containing path traversal patterns targeting WordPress plugin directories
• Monitor web server logs for suspicious requests to /wp-content/plugins/smart-agreements/ containing encoded traversal sequences
• Deploy intrusion detection signatures to identify LFI exploitation attempts against WordPress installations
• Use security plugins that audit file inclusion operations and alert on anomalous behavior

Monitoring Recommendations

• Enable verbose logging for WordPress and the web server to capture detailed request parameters
• Configure alerting for any requests to plugin endpoints containing null bytes, traversal sequences, or PHP wrapper protocols
• Implement file integrity monitoring on sensitive configuration files like wp-config.php
• Review access logs regularly for patterns consistent with LFI reconnaissance and exploitation

How to Mitigate CVE-2025-39462

Immediate Actions Required

• Deactivate and remove the Smart Agreements plugin immediately if running version 1.0.3 or earlier
• Audit web server logs for evidence of exploitation attempts against this vulnerability
• Review WordPress configuration files for any signs of unauthorized access or modification
• Implement WAF rules to block path traversal attacks as a defense-in-depth measure
• Consider rotating database credentials if there is any indication of wp-config.php exposure

Patch Information

At the time of this advisory, no patch has been confirmed for the Smart Agreements plugin. Users should check the Patchstack Vulnerability Report for the latest remediation guidance. If no update is available, removal of the plugin is strongly recommended.

Workarounds

• Completely disable or uninstall the Smart Agreements plugin until a patched version is available
• Implement strict WAF rules to filter directory traversal patterns on all requests to WordPress plugin directories
• Use PHP open_basedir restrictions to limit file access scope for the web server process
• Enable WordPress security hardening by restricting file permissions and disabling file editing through the admin interface
• Consider using a WordPress security plugin that provides virtual patching capabilities for known vulnerabilities

# Example Apache mod_security rule to block path traversal
SecRule REQUEST_URI "@contains ../" "id:1001,phase:1,deny,status:403,msg:'Path Traversal Attempt Blocked'"

# Restrict PHP open_basedir in php.ini or .htaccess
# php_value open_basedir /var/www/html:/tmp