CVE-2026-28097: ThemeREX Artrium LFI Vulnerability

CVE-2026-28097 Overview

CVE-2026-28097 is a Local File Inclusion (LFI) vulnerability in the ThemeREX Artrium WordPress theme. The vulnerability stems from improper control of filename for include/require statements in PHP, allowing attackers to include arbitrary local files on the server. This flaw enables unauthenticated remote attackers to potentially read sensitive configuration files, access credentials, or chain with other vulnerabilities to achieve remote code execution.

Critical Impact

Unauthenticated attackers can exploit this LFI vulnerability to read sensitive files from WordPress installations, potentially exposing database credentials, API keys, and other sensitive configuration data stored on the server.

Affected Products

• ThemeREX Artrium WordPress Theme versions through 1.0.14
• WordPress installations using the vulnerable Artrium theme

Discovery Timeline

• 2026-03-05 - CVE-2026-28097 published to NVD
• 2026-03-05 - Last updated in NVD database

Technical Details for CVE-2026-28097

Vulnerability Analysis

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

The attack can be executed remotely over the network, though exploitation requires specific conditions to be met, contributing to the complexity rating. No authentication or user interaction is required, making this vulnerability particularly dangerous for internet-facing WordPress installations.

Root Cause

The root cause of this vulnerability lies in insufficient input validation within the Artrium theme's PHP code. When processing user-controlled input for file inclusion operations, the theme fails to implement proper sanitization to prevent directory traversal sequences (such as ../) or validate that the requested file is within an allowed directory. This allows attackers to escape the intended directory context and access files outside the web root or within sensitive directories.

Attack Vector

The attack vector is network-based, allowing remote exploitation without authentication. An attacker crafts malicious HTTP requests containing path traversal sequences to manipulate the file inclusion logic.

A typical exploitation scenario involves sending requests with directory traversal patterns to access sensitive files:

The vulnerability allows attackers to traverse directories using sequences like ../ to escape the intended file path and include arbitrary local files. Common targets include /etc/passwd for system enumeration, wp-config.php for database credentials, and log files that may contain sensitive information. When exploited, the server processes the traversal sequences and includes the attacker-specified file, potentially exposing its contents or executing PHP code within included files.

Detection Methods for CVE-2026-28097

Indicators of Compromise

• HTTP requests to WordPress theme endpoints containing path traversal sequences such as ../, ..%2f, or encoded variants
• Web server logs showing attempts to access system files like /etc/passwd, /etc/shadow, or wp-config.php through theme-related URLs
• Unusual access patterns targeting the Artrium theme directory with suspicious query parameters

Detection Strategies

• Deploy Web Application Firewall (WAF) rules to detect and block path traversal attempts in HTTP requests targeting WordPress theme endpoints
• Monitor web server access logs for requests containing directory traversal patterns or attempts to access files outside the web root
• Implement file integrity monitoring on WordPress installations to detect unauthorized access or modification of sensitive files
• Use intrusion detection systems configured with signatures for LFI exploitation attempts

Monitoring Recommendations

• Enable detailed logging on web servers to capture full request URIs and query parameters for forensic analysis
• Configure SIEM alerts for patterns matching LFI exploitation attempts against WordPress installations
• Regularly review access logs for anomalous requests targeting theme file inclusion endpoints

How to Mitigate CVE-2026-28097

Immediate Actions Required

• Identify all WordPress installations using the ThemeREX Artrium theme version 1.0.14 or earlier
• Consider temporarily deactivating the Artrium theme until a patched version is available
• Implement WAF rules to block requests containing path traversal sequences targeting the vulnerable endpoints
• Review web server logs for evidence of prior exploitation attempts

Patch Information

Users should monitor the Patchstack WordPress Vulnerability database for updates regarding patches from ThemeREX. Update the Artrium theme to the latest version once a security patch is released by the vendor.

Workarounds

• Deploy a Web Application Firewall with rules configured to block path traversal patterns in requests to WordPress theme directories
• Restrict access to the WordPress admin and theme directories using server-level access controls
• Implement PHP open_basedir restrictions to limit file system access for the PHP process
• Consider switching to an alternative WordPress theme until the vendor releases a security patch

# Example Apache .htaccess rules to block common LFI patterns
RewriteEngine On
RewriteCond %{QUERY_STRING} (\.\./|\.\.) [NC,OR]
RewriteCond %{QUERY_STRING} (\.\.%2f|%2e%2e) [NC]
RewriteRule .* - [F,L]

# PHP open_basedir configuration in php.ini
# open_basedir = /var/www/html/:/tmp/