CVE-2019-25574: Njtech Greencms Path Traversal Flaw

CVE-2019-25574 Overview

Green CMS 2.x contains a path traversal vulnerability that allows authenticated attackers to download arbitrary files and directories by injecting directory traversal sequences. Attackers can manipulate the theme_name parameter in the themeexporthandle action or supply base64-encoded file paths to the downfile action to retrieve sensitive files outside intended directories.

Critical Impact

Authenticated attackers can exfiltrate sensitive configuration files, database credentials, source code, and other critical system files from affected Green CMS installations, potentially leading to full system compromise.

Affected Products

• njtech greencms 2.x
• Green CMS installations with exposed theme export functionality
• Systems running vulnerable versions accessible via network

Discovery Timeline

• 2026-03-21 - CVE CVE-2019-25574 published to NVD
• 2026-03-24 - Last updated in NVD database

Technical Details for CVE-2019-25574

Vulnerability Analysis

This path traversal vulnerability (CWE-22) exists within Green CMS 2.x's theme management functionality. The application fails to properly sanitize user-supplied input when processing theme export requests, allowing attackers to escape the intended directory structure and access arbitrary files on the server.

The vulnerability manifests through two distinct attack surfaces: the themeexporthandle action which accepts a theme_name parameter, and the downfile action which processes base64-encoded file paths. In both cases, directory traversal sequences such as ../ are not adequately filtered, enabling path manipulation attacks.

Successful exploitation requires authentication to the CMS, but once authenticated, an attacker can retrieve any file readable by the web server process, including configuration files containing database credentials, application source code, and potentially sensitive user data.

Root Cause

The root cause stems from insufficient input validation in the theme export and file download handlers. The application accepts user-controlled path parameters without properly validating that the resolved path remains within the expected directory boundaries. The use of base64 encoding in the downfile action may have been intended as an obfuscation measure but provides no actual security benefit against path traversal attacks.

Attack Vector

The attack is network-based and requires low-privilege authenticated access to the Green CMS administrative interface. An attacker can craft malicious HTTP requests targeting either the themeexporthandle action with traversal sequences in the theme_name parameter, or the downfile action with a base64-encoded path containing traversal sequences.

For example, an attacker could request paths like ../../../../../../etc/passwd or the base64 equivalent to read system files. The downloaded content would reveal sensitive information that could be leveraged for further attacks, including privilege escalation or lateral movement within the compromised environment.

Technical details and proof-of-concept information are available in the Exploit-DB #46245 advisory.

Detection Methods for CVE-2019-25574

Indicators of Compromise

• HTTP requests to Green CMS containing themeexporthandle with unusual or traversal-sequence-containing theme_name values
• Requests to the downfile action with base64-encoded payloads that decode to paths containing ../ sequences
• Web server access logs showing repeated requests for theme export functionality from a single authenticated session
• Unusual file access patterns in web server or application logs indicating reads outside the CMS directory structure

Detection Strategies

• Deploy web application firewall (WAF) rules to detect and block path traversal sequences including ../, ..\, and their URL-encoded variants
• Monitor HTTP request parameters for base64-encoded strings that decode to contain directory traversal patterns
• Implement file integrity monitoring on sensitive configuration files to detect unauthorized access attempts
• Review authentication logs for accounts making repeated requests to theme management endpoints

Monitoring Recommendations

• Enable verbose logging on the Green CMS application and web server to capture full request details including parameters
• Configure alerts for access to sensitive system files such as /etc/passwd, .htaccess, and database configuration files
• Monitor for elevated file download activity from authenticated CMS sessions
• Implement behavioral analysis to detect anomalous patterns in theme export functionality usage

How to Mitigate CVE-2019-25574

Immediate Actions Required

• Restrict access to the Green CMS administrative interface to trusted IP addresses only
• Review authentication logs for suspicious activity and revoke access for any compromised accounts
• Audit file permissions to ensure the web server process cannot read sensitive files outside the CMS directory
• Consider temporarily disabling theme export functionality until a patch is applied

Patch Information

No official vendor patch information is currently available for this vulnerability. Organizations should monitor the GreenCMS Official Site and the GreenCMS GitHub repository for security updates. The VulnCheck Advisory provides additional technical details about this vulnerability.

Workarounds

• Implement a reverse proxy with path validation rules to block requests containing directory traversal sequences
• Apply web server configuration hardening to restrict file access to the CMS document root using open_basedir (PHP) or equivalent directives
• Deploy a web application firewall with rules specifically targeting path traversal attack patterns
• Consider migrating to an actively maintained CMS if Green CMS is no longer receiving security updates

# Example: Apache mod_rewrite rule to block path traversal attempts
RewriteEngine On
RewriteCond %{QUERY_STRING} (\.\./) [NC,OR]
RewriteCond %{QUERY_STRING} (\.\.\\) [NC]
RewriteRule .* - [F,L]

# Example: PHP open_basedir restriction in php.ini or .htaccess
php_admin_value open_basedir /var/www/greencms/